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Displays Hardware

Does Your LCD Play Catch-Up To Your Mouse? 691

Dishes of Ryan writes "I fell in love with the idea of an LCD monitor, so I ended up buying a nice, shiny Dell 2001FP. However, nowhere, and I mean *nowhere* did I read about LCDs having an input lag on them. For instance, if I scoot the mouse across the screen, there is a noticeable delay between when I move the mouse and when the cursor moves. To prove it to people, made a video showing exactly what I mean. You can almost forget being king of the hill on twitch FPS games like Unreal Tournament. Are there any other Slashdotters out there that are as annoyed as I am? What did you do?"
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Does Your LCD Play Catch-Up To Your Mouse?

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  • by AKAImBatman ( 238306 ) * <<moc.liamg> <ta> <namtabmiaka>> on Sunday September 26, 2004 @07:54PM (#10358326) Homepage Journal
    No offense, but you need to get another monitor. I notice no "lag" between my iBook and CRTs, nor do I notice any lag on my new 17" KDS for my desktop. Having developed a few video games and GUIs, I have a fairly well trained eye. I can see the problem in the video, but I see no such problem on my systems.

    Conclusion? Dell buys parts from the lowest bidder. Ergo, they are the lowest quality. Therefore, you need a better monitor.

    Sorry.
    • by Desert Raven ( 52125 ) on Sunday September 26, 2004 @07:59PM (#10358384)
      I'll second this. I'm running a Sumsung 193v flat panel bought at Sam's club, on an old dual PIII-800 with an NVIDIA GeForce FX 5200 card.

      No lag here, at all. And this stuff ain't exactly cutting-edge.

      Did it occur to you that maybe you have a hardware problem with *your* system?
    • by AKAImBatman ( 238306 ) * <<moc.liamg> <ta> <namtabmiaka>> on Sunday September 26, 2004 @08:00PM (#10358400) Homepage Journal
      I just thought of something you might want to try. LCDs are a bit different than CRTs in that they are completely digital. Since the monitor is digital, it sometimes requires calibration when used with an analog connector. Check your manufacturers specs for the EXACT resolution AND refresh rate that they recommend. The monitor will run in other modes, but it supposedly won't do them as well.

      Once you've set your resolution and refresh rate, be sure to use the auto-adjust button if your monitor has it. When I first got mine, I thought the picture looked like crap. Then I found the auto-adjust. With a push of a button, I suddenly saw the crispest text I'd ever seen in my life. Quite an improvement over CRT displays. :-)
      • by Waffle Iron ( 339739 ) on Sunday September 26, 2004 @08:39PM (#10358755)
        One thing I noticed is that if you have a screen full of anti-aliased text, the auto adjust may not have enough edges to crunch on. I have a big bitmap of alternating black and white pixels that I put up to test the monitor's synch to the pixel clock.

        If I autoadjust while showing normal windows, the bitmap will usually still have fuzzy areas when I pull it up. If I autoadjust while the bitmap is being displayed, the monitor is able to lock onto it perfectly. The text looks noticeably better with a perfect lock, especially when using sub-pixel sampling on the fonts, which needs pixel-perfect alignment to work properly.

        I have a shortcut to this image on my systems because I have a KVM switch, so I need to autoadjust a lot. No two systems have the exact same video timings.

        • by Doppler00 ( 534739 ) on Sunday September 26, 2004 @10:02PM (#10359315) Homepage Journal
          sub-pixel sampling on fonts does not work very good at all unless you use a DVI connector for your LCD. I changed from a VGA to a DVI connector on my LCD panel at work and the difference is astounding. I'm still amazed that 90% of consumers are completely oblivious to this difference. Not to single you out specifically, but I'm tired of the average consumer being ignorant of the differences between video connection standards.

          BTW, companies now make excellent DVI/USB KVM switches, so there is no execuse to use a VGA connection on a LCD panel anymore.
          • sub-pixel sampling on fonts does not work very good at all unless you use a DVI connector for your LCD.

            Funny, the sub-pixel antialiasing looks virtually identical on my laptop, my pair of aging 15 inch LCD panels, and every other LCD I've tried. All except for the laptop(s) are analog.

            I changed from a VGA to a DVI connector on my LCD panel at work and the difference is astounding.

            If you are seeing that much of a difference you might want to learn how to adjust you LCD. So far, every single time

        • by Anonymous Coward on Sunday September 26, 2004 @11:11PM (#10359712)
          Waffle Iron,

          THANK YOU! Excellent post my friend. I just created a small bmp in paint with different sized black squares on a white background, then tiled it for my background -> Autoadjusted my LCD.

          It looks fucking fantastic, text is smooth and clear, unbelievable. Thanks a million man, most useful post I've read on slashdot. Note, and this isn't even at my LCD's native resolution (1280x1024, whereas I am running 1280x960). Amazing, didn't think this was possible.

        • by Kizzle ( 555439 ) on Monday September 27, 2004 @02:56AM (#10360527)
          THANK YOU. Awesome trick. I put up the images as you described them. These worked for me. I did notice my LCD acting really weird when these images were being displayed. I don't recommend keeping the image on the monitor for any longer than needed. http://www.hackermedia.net/downloads/lcd-cal
    • Um, no. (Score:5, Informative)

      by autopr0n ( 534291 ) on Sunday September 26, 2004 @08:09PM (#10358497) Homepage Journal
      I've used lots of LCDs, including plenty of DELL LCDs. The LCDs we've used at work were faded, and the colors looked awful after a copule of years. but I've never never seen any kind of lag like this in any kind of monitor.

      My guess is that there is something wrong with the video drivers, or the mouse drivers, or some other part of his computer that's causing these problems.

      I can't see the vid because the file is apperantly slashdotted.
      • Re:Um, no. (Score:5, Insightful)

        by kzinti ( 9651 ) on Sunday September 26, 2004 @09:48PM (#10359230) Homepage Journal
        My guess is that there is something wrong with the video drivers, or the mouse drivers, or some other part of his computer that's causing these problems.

        If I remember the specs I saw when I was shopping for an LCD monitor about 18 months ago, LCD update rates are characterized in tens of milliseconds. The ones I was considering were in the 20 to 28 ms range. That's between one and two screen refreshes at 60 Hz. That's fast enough not to be noticeable.

        If the monitor were causing the mouse to have a noticable lag, then everything else would appear to lag too. The guy needs to do some other tests - if he brings up a window and types, do the characters appear to be delayed too?

        I'm with you - I think it's his mouse driver or some sort of strange interaction between the mouse driver and something he installed with the new drivers.
        • Re:Um, no. (Score:5, Funny)

          by suckmysav ( 763172 ) <suckmysav&gmail,com> on Sunday September 26, 2004 @11:41PM (#10359869) Journal

          "The guy needs to do some other tests - if he brings up a window and types, do the characters appear to be delayed too?"



          Reminds me of a guy who bought his dot-matrix printer in for repair twice because it would not print the letter K. No amount of testing was enough to convince him that this was simply not possible. It turned out his keyboard had a faulty K key, and the K was not appearing on his screen either.

    • by Spy Hunter ( 317220 ) on Sunday September 26, 2004 @08:12PM (#10358528) Journal
      I have this monitor, and it causes no lag on my machine. Dragging windows is just as instant as it is on a CRT, and most games are quite responsive. I'll admit I haven't put it side-by-side with a CRT, but I am quite sensitive to mouse lag (I refuse to use a USB mouse on my machine because for some reason it causes noticable lag, perhaps due to dodgy USB hardware/drivers).

      P.S. This monitor is awesome and I would recommend it to anybody. Great for gaming, watching movies, anything.

    • Mirror (Score:4, Informative)

      by jagilbertvt ( 447707 ) on Sunday September 26, 2004 @08:18PM (#10358591)
  • display or drivers? (Score:3, Informative)

    by v1 ( 525388 ) on Sunday September 26, 2004 @07:55PM (#10358336) Homepage Journal
    I wonder if it's the display that's lagging, or the video drivers? The last time I recall seeing an LCD display "lag" was back before the days of TFT screens, where your mouse would "submarine". (disappear while it was on the move)
    • I wonder if it's the display that's lagging, or the video drivers? The last time I recall seeing an LCD display "lag" was back before the days of TFT screens

      This seems to be a much more sensible explanation for the apparent lag. Even early TFT displays suffer from comparitively slow screen update intervals.

      How the heck did this question make it past the editorial filter anyway? The idea that LCD displays are susceptible to some kind of input device lag specifically (as opposed to any other kind of state
      • by autopr0n ( 534291 ) on Sunday September 26, 2004 @08:12PM (#10358529) Homepage Journal
        Easy. Slashdot editors are idiots who don't care a wit for the content on the site. I mean really, this site could have so much potential, but it's really been squandered by the creators. Average people who don't want to cede control to people who could actualy do a good job.

        /rant.
        • I mean really, this site could have so much potential, but it's really been squandered by the creators.

          Funny how they've got all that money for what they did, and managed to go from a few hundred users in the first few months to hundreds of thousands (not to mention the countless people that read and don't bother with use accounts).

          I find it amusing how everyone thinks they could do a better job, but when you only have very few people sorting through thousands of story submissions, it isn't that easy.
  • Reader Reviews (Score:3, Insightful)

    by the eric conspiracy ( 20178 ) on Sunday September 26, 2004 @07:56PM (#10358340)
    When I bought my LCD monitor I found all kinds of information in user reviews online. Check out New Egg, Amazon, etc. for all kings of discussion of this exact issue.

    • Re:Reader Reviews (Score:5, Interesting)

      by Jacer ( 574383 ) on Sunday September 26, 2004 @08:13PM (#10358553) Homepage
      Never, under any circumstances base buying decisions off of reviews from Newegg. Half the reviewers state they're first time system builders with no real idea of what there doing. The other half try to sound like they know what they're talking about, but obviously have no clue, or are just flat out lieing. Then you have the problem that newegg removes the reviews that are less than pleasant. Your best bet is to read a site that focuses on reviews and sells no hardware. Maybe Slashdot could start a hardware review section and do some unbiased hard journalism!
      • *Maybe Slashdot could start a hardware review section and do some unbiased hard journalism!*

        how would it help with the problem of getting misinformation from clueless people who heard couple of cyberlegends, didn't read to the end of the blurb and never opened a computer in their life?

        speaking of which, 80% of the comments under this article alone are totally clueless as to the what the actual problem was that the guy was having and as a consequence tell him to check the batteries on the mouse and shit li
  • by Thai-Pan ( 414112 ) on Sunday September 26, 2004 @07:56PM (#10358345) Journal
    I've built countless systems with various high and low end LCD screens with no such lag. The worst screen I've encountered had the typical old-generation ghosting, but I've never seen input lag.
  • by Stevyn ( 691306 ) on Sunday September 26, 2004 @07:59PM (#10358374)
    I'd recommend popping in Knoppix and see how it works. It will probably pick an open driver made for your graphics card family. You say this happens with the mouse, what about typing?
  • No sir... (Score:3, Insightful)

    by Rew190 ( 138940 ) on Sunday September 26, 2004 @08:00PM (#10358388)
    I've had zero problems on both of my laptops and every LCD I've ever used. Something's screwy with your hardware. It's rather sad that Slashdot posted this as a front pager...
  • by Nuclear Elephant ( 700938 ) on Sunday September 26, 2004 @08:00PM (#10358392) Homepage
    What did you do?

    I posted a 800K movie of it on Slashdot so I could suck up all the Internet's available bandwidth and make everyone else's game run at the same fps as mine. =)
  • by flamechocobo ( 792168 ) on Sunday September 26, 2004 @08:02PM (#10358421)
    That monitor is actually a BenQ monitor with Dell's name on it. It's a great monitor, and has a 16ms response time, so it shouldn't lag at all in normal use. You should try video drivers or maybe even the mouse itself. There simply is no reason a good monitor such as that one (congratulations on your purchase. That's the best cost to performance monitor out right now.) should show lag in a normal situation. I have used a 25ms LCD, and it doesn't lag in normal use. Call Dell after if driver's don't work.
  • Not an LCD problem (Score:3, Insightful)

    by mpoulton ( 689851 ) on Sunday September 26, 2004 @08:02PM (#10358426)
    That sounds much more like an issue with your computer than with your monitor. Does it do this with a CRT running the same resolution and refresh rate? I would bet so. LCDs have slower image response time (pixel rise/fall) than CRTs, but there is no significant delay between the time a signal reaches the monitor and the time it is displayed. In fact, implementing such a delay would be quite a challenge -- the information would have to be stored somewhere between the time it is sent to the monitor and the time it is displayed. This would require significant memory in the monitor to buffer several frames of video. Monitors don't do this.
  • by Silvers ( 196372 ) on Sunday September 26, 2004 @08:06PM (#10358464)
    It's the buffering in the driver.

    Flat Panels *will* ghost and blur, however they do not lag.

    What causes this is buffering of execution commands in the drivers, which makes some games at certain resolutions lag really really bad on input.

    Change drivers, and it will usually go away.
  • by coupland ( 160334 ) * <<moc.liamtoh> <ta> <esahcd>> on Sunday September 26, 2004 @08:14PM (#10358557) Journal
    Since when was /. an online PC troubleshooting forum? Any doofus knows LCD screen don't suffer from "lag" -- why doesn't he call Dell or ask on a newsgroup, not take out an article on the front page of Slashdot???
  • by jdkane ( 588293 ) on Sunday September 26, 2004 @08:19PM (#10358601)
    /.TS> Yes hello, Slashdot Tech Support speaking. How may I help you today?

    DoR> Um, my mouse lags on my Dell LCD.

    /.TS> That's what we're here for. News for Nerds, Stuff that matters. Try installing Linux and then get back to us with the results.

    DoR> How's that gonna' help?

    /.TS> Sorry, you're Offtopic -1. I see a better story coming along. Good bye and thank you for calling.

  • by The Fink ( 300855 ) <slashdot@diffidence.org> on Sunday September 26, 2004 @08:25PM (#10358646) Homepage
    ... and have never, ever, seen this problem - and we do push these screens pretty much as hard as you'd want to (it's an aircraft command and control environment). Using either DVI or analogue signals, coming out of Dell hardware (my employer's preferred supplier).

    Might be something 2001-specific, but from the description given, that sounds like an issue I'd peg on something else, not on the display.
  • by cybermint ( 255744 ) * on Sunday September 26, 2004 @08:27PM (#10358669)
    Site Mirror: Click here [antigamer.com].
    Video Only: Click here [antigamer.com].
  • by bigberk ( 547360 ) <bigberk@users.pc9.org> on Sunday September 26, 2004 @08:32PM (#10358703)
    I bought a Samsung SyncMaster 171v two years ago, and brought it home fearfully waiting for the ghosting I had heard about with LCD monitors. No such experience. In my day-to-day work I don't notice any GUI delays that can be blamed on the monitor. And even when playing games (like Enemy Territory) the monitor performs beautifully.

    But I have seen other people with LCD monitors that don't seem to work as well with fast moving objects. The SyncMaster wasn't a particularly expensive model or anything, but it definitely performs well.
  • by macshit ( 157376 ) * <[snogglethorpe] [at] [gmail.com]> on Sunday September 26, 2004 @08:35PM (#10358725) Homepage
    I'll join the chorus of people saying "no". Either it's a problem somewhere else in your system, or a really crappy LCD.

    I used to not like LCD monitors, especially the kind that use the analogue video out, but at work I got an NEC MultiSync LCD 1760v (17", 1280x1024 -- I know, yesterday's news, but a great step up for me :-), which has made a complete convert out of me.

    Not only does it have far better contrast and brightness than other LCD monitors I've used, but it has no ghosting of any kind, and tracks the analogue video output of my computer flawlessly. Even the industrial design is great, much better than typical "we've got a really expensive CAD system and no design sense whatsoever" designs, and I'd say on par with Apple's wonderful creations (without Apple's tendency to be a bit poncy ... "we're stylish and we're not going to let you forget it!").

    The display gamma seems to be much different than my old CRT, so it did take a bunch of adjustment to get pictures looking the same.

    Anyway, 3 thumbs up for the 1760V from me (this model is a few years old I think).
  • by WindBourne ( 631190 ) on Sunday September 26, 2004 @08:38PM (#10358744) Journal
    Hey, will even throw in shipping. :)
  • Questions: (Score:3, Insightful)

    by xigxag ( 167441 ) on Sunday September 26, 2004 @09:09PM (#10358944)
    Does this effect only happen upon mouse movement, or do you detect the same problem while playing a video?

    Did you try setting your monitor resolution to 800X600 or decreasing your colors to 16-bit?

    Did you try resizing the window with your keyboard (e.g. in Windows using ALT+Space to activate the System menu)?

    Did you try seeing what happens with a different OS? (e.g Knoppix)

    Did you try changing your mouse drivers?

  • by ImTwoSlick ( 723185 ) on Sunday September 26, 2004 @09:25PM (#10359071)
    However, I have no problems with any kind of lag. This includes all video connections.
  • by halo1982 ( 679554 ) * on Sunday September 26, 2004 @09:28PM (#10359097) Homepage Journal
    At my dad's office we have a computer powered by a Parhelia hooked up to two UltraSharp 2001FPs (both through DVI...haven't tried it with analog cause whats the point) and I have never seen anything like this. They're just as good as a CRT (for CAD anyway) and the screens are gorgeous. My guess is USAR ERRAR
  • by Mulletproof ( 513805 ) on Sunday September 26, 2004 @09:32PM (#10359129) Homepage Journal
    Now you've got me curious... No offense to the submitter, but this is obviously an isolated problem. Asking the average wage slave techie down at Best Buy could have confirmed this. Infact, nearly everybody on Slashdot has confirmed it to one degree or another. Soooo... Why is this frontpage news again? Will Slashdot start answering my unique one-shot hard drive problems now too? Hi, my name is Ed and my HDD is making an odd 'kerchunk' sound when it starts up. Have any other Slashdot users noticed this with their HDDs????? Why not? Let's convert the front page to miscellaneous hardware bug reports... Or not?

    I'd submit to you that this question should have been handed off to any number of the flatscreen FAQ sites out there, especially given how unique the problem is. We're not exactly talking about ipod batteries here.
  • Dude..... (Score:5, Funny)

    by moosesocks ( 264553 ) on Sunday September 26, 2004 @09:34PM (#10359147) Homepage
    Dude, no human has reflexes like that.

    You're either:
    a) Not human
    b) Jedi
    c) Stoned/Drunk

    Go become a fighter pilot or something like that.
  • by Mean_Nishka ( 543399 ) on Sunday September 26, 2004 @10:02PM (#10359317) Homepage Journal
    I got a kick out of this story because I had experienced some mouse trouble when I first got my Dell 2001FP.

    For some reason, all of my games ran like crap after picking up the display... Game after game simply ran like a slug after the LCD was added to the mix and I couldn't figure out what the problem was.

    I finally noticed that if I took my hand off the mouse, things ran smoother.. After some trial and error I discovered my first generation optical Intellimouse Explorer didn't like the USB hub on the Dell monitor (I plugged it into the 2001FP's USB ports to add some slack on the mouse cable). While the problems were not readily apparent on the 2D apps, they were incredibly apparent in the games.

    So after moving the mouse back to the PC's main USB ports, everything improved dramatically. It gave me an excuse to pick up that new fancy Logitech laser deal.

  • Here's my guess.... (Score:3, Interesting)

    by NerveGas ( 168686 ) on Sunday September 26, 2004 @10:04PM (#10359327)

    It's your mouse drivers.

    I've got a wireless mouse that has absolutely no lag under Windows - but try playing a DirectX game, and it's got tons of lag. Because I rarely game on that machine, I haven't taken the time to figure it out - but if I plug a regular USB mouse into it, it works just fine.

    steve
  • my experience (Score:3, Informative)

    by sewagemaster ( 466124 ) <sewagemaster@NOSpAm.gmail.com> on Sunday September 26, 2004 @10:33PM (#10359493) Homepage
    my university recently purchased something like 8 new labs filled with these monitors, and I havent noticed any sort of the lag mentioned in the article. at home i use a samsung syncmaster 172N and i dont notice any of that either. I think it's best to have the monitor exchanged...

    fyi, the new school computers run P4 2.8C and my home computer runs P4 3.0C -- but i doubt this has anything to do with my "lack" of lag...
  • by batobin ( 10158 ) on Sunday September 26, 2004 @10:36PM (#10359517) Homepage
    Since everyone is skeptical, I would like to chime in and say that I'm having the exact same problem (same Dell monitor, too). Perhaps the addition of my specs will shed some light on the culprit.

    So far I've tried two different video card setups (both MacOS X on a dual 1GHz g4 power mac). The first was the GeForce 4MX card that shipped with the computer. I was using analog output to analog monitor input. Thinking the lag could be the result of analog to digital conversion, I purchased the ATI Radeon 9000 with digital output.

    I'm currently using the digital video output to digital monitor input. The problem is still there. Both cards are AGP, and I never experienced a lag before buying the Dell.

    Hopefully this helps. If I've left out something important, let me know.
  • Oops, sorry (Score:4, Funny)

    by Tenebrious1 ( 530949 ) on Sunday September 26, 2004 @10:37PM (#10359520) Homepage
    Sorry, that's my keylogger that's causing the lag; it's writing all your keyboard inputs directly to my web server instead of logging and uploading the log, and that's slowing down your system.

    Please type "updateme" on your keyboard, and that will tell the keylogger to automatically update itself. Once it's updated, you shouldn't notice any lag at all.

  • by myov ( 177946 ) on Sunday September 26, 2004 @10:47PM (#10359588)
    My LCD's (2 identical units) have no lag over DVI or VGA.

    With NTSC video, the delay is noticable. Any video with motion will blur (rolling credits, hockey ads around the edge of the ice - not that it's a problem now.) Audio is completely out of sync, and I need an audio delay somewhere to make things line up.

    FWIW, the NTSC input is directly into the monitors, not through an external converter.
  • by mrshowtime ( 562809 ) on Sunday September 26, 2004 @10:56PM (#10359643)
    I have owned several Dell displays and have had no problems. I HAVE had lot of problems with "mice" over the years. In fact I had to replace my first generation Intellimouse optical wireless as it just did not work well with my new system. I would put the blame on the mouse, more than the LCD screen. It's amazing that this obviously minor problem has gotten so much attention: I.E. try another mouse before filming yourself and complaining to the entire internet community. Heck, I was having problems all around till I unplugged my bluetooth adapter.
  • Front page? (Score:5, Insightful)

    by AyeRoxor! ( 471669 ) on Monday September 27, 2004 @03:39AM (#10360653) Journal
    I submit articles about the chips in "missile defense" systems being faulty, and they're shelved. Someone incorrectly configures their cheap monitor and it makes front page? WTF?

    Here's the amazing answer: If it sucks, take it back.

    Shit.

  • Nowhere? (Score:4, Informative)

    by Vo0k ( 760020 ) on Monday September 27, 2004 @03:44AM (#10360666) Journal
    I just don't get it. This is the most basic thing you check with the LCD display.
    Some people out there still look for higher vertical refresh rate at LCD. *sigh*

    Common features:
    Diagonal
    Color quality/reliablity [1]
    GFX input capablity. (VGA/DVI/S-Video etc)
    No missing (dark) pixels.

    Important with CRT:
    Maximum resolution
    Maximum Vertical refresh rate at resolution you most frequently use.[2]
    Image sharpness
    Black pitch [3]
    Flatscreen/Trinitron(cyllinder)/Sphere screen.

    Important with LCD:
    Default (non-interpolated) resolution [4]
    <b>Pixel switch-on time</b> (display lag)
    Pixel switch-off time (ghosts)
    Vieving polarization angle[5]
    Maximum brightness
    Working temperature range
    backlight LED lifetime [6]

    [1] These ARE different. LCDs have sugar-sweet beautiful colors, that can't be repeated in print, that's why LCDs are the worst choice for a graphician, while your average end user will enjoy the more-than-lifelike graphics immensely
    [2] On CRT image at 25HZ hurts your eyes badly. On LCD you can freely read books at 25HZ, the refresh rate doesn't mean cycles between switching the image on and off, but between changes to constant content.
    [3] Is black really black or just a shade of grey?
    [4] LCDs have one fixed resolution at which they look great, all the other resolutions suck as computer output pixels don't match display pixels.
    [5] If you don't look straight ahead at the screen, some colors just go dark on some screens.
    [6] LCD doesn't shine. LCD switches half-transparent pixels on and off, masking the white backlight LEDs off. Without backlight you'll see hardly anything. It's the backlight that eats up most of your batteries too. And it's the LEDs that die first if the screen doesn't get broken/scratched etc first.
  • by Qbertino ( 265505 ) <moiraNO@SPAMmodparlor.com> on Monday September 27, 2004 @03:45AM (#10360670)
    Since you're posting a wmv (which is bad attitude) I can't watch it. But from your description I'd say that's very strange indeed.
    I guess you're using Windows XP. It could be that the Monitor specs/drivers are changed automatically when you switch back and forth and that the one for that LCD causes the lag. Monitors are Plug and Play too, so that's very likely. I'd say you do the Knoppix test some others have recommended already. It could also be an USB Hub in the Monitor (again, don't know if you have one because you've posted a wmv) that causes trouble (interference) via the USB port when the panel is on, thus distorting and lagging the mouse signal.

    Those are my two guesses.

    And once again, if you think it's a good idea to post stuff like this on /., do please have the common decency to use a video format that's open and free for all to watch. Thank you.
  • by Dishes of Ryan ( 816384 ) on Monday September 27, 2004 @09:12AM (#10362022)

    First of all, thank you, everybody, for taking a look at this. I received a characteristically Slashdotty wealth of "you're an idiot" replies, and a good number of "I didn't read the full article and/or watch the video so I'm jumping to conclusions" replies as well. =) Those of you that read the article and offered your genuine insight, thank you.

    It's all fine, though. I'd like to answer a few randomly culled questions here, and also summarize what I've found based on all the feedback so other potential LCD owners can get a better feel for what they're up against.

    1. It's not the mouse. If you look at the video (which many of you probably couldn't), you'll see that I have a dual-head setup that includes a CRT. It's lightning-quick responsive on the CRT.
    2. As I mentioned in the full article, even when I use a single head setup with just the LCD, the same lag is present. And to those that guarantee switching to a single head CRT on the system will show the same lag. I've tried that in the past, and, again, the CRT is lightning-quick.
    3. I'm running at the native resolution (1600x1200) with things like ClearType off, running over DVI. For that matter, if I do switch it to a non-native res, it still exhibits the same level of lagginess. Same goes with switching it to analog. Same lag.
    4. I've used this LCD with many different computers (laptops, other desktop machines) and the problem replicates itself on every machine, regardless of OS or drivers.
    5. I've seen the same lag on every LCD I've ever seen or used, although the problem is not as great as this one. Examples are my laptop, work computers, family computers, etc. If you think that you don't have a lag, you probably do (compare with a CRT), but you're probably blessed with one that is minimal enough to not be immediately perceptible. My laptop is much more useable for things like games because the lag isn't nearly as bad.
    6. People that use this LCD for gaming that claim they have no problems, I'd suggest you try switching back to a CRT for a comparison. The "feel" will likely immediately clue you in to the difference.
    7. It's not the driver, as guaranteed as you'd like to say it is. I've tried every driver on the planet. Also, see #4 above.
    8. Others recognize this to be an issue as well, with their 2001FPs and others. Some of the comments say that they hate LCDs for this very reason. A good number of people who primarily game have returned their LCDs because it messes them up on games like CS or Unreal Tournament.
    9. To those that think I should have taken this to a troubleshooting forum on Dell or elsewhere, there was apparently an issue posted about it on Dell's site. Someone's solution was to bring it down to a 1280x1024. See #3. Other than Dell's site, I was unable to find mention of it anywhere else, even though, yes, GIMF.

    The overall summary, which you may or may not agree with is: Most LCDs are laggier than CRTs (I'd be jumped in an alley if I went as far as to say *all* LCDs are, but I try to avoid sweeping generalizations). Do your own tests, and come to your own conclusions. If you're a gamer, be careful. And lastly, my Dell 2001FP may in fact be one of the laggiest LCDs in existence, *or* I just received a defective unit.

    Thanks again, everybody, for the replies. I hope this helps some people. I know that I at least saw one person in the comments that learned something new, although it was, in fact, for something unrelated to the immediate post. =)

  • by yeremein ( 678037 ) on Monday September 27, 2004 @09:17AM (#10362052)
    If you're running games at the native resolution of your display (1600x1200), the most probable reason for the lag you're seeing is that your video card simply can't keep up. It takes a pretty beefy video card to push that many pixels per frame. Try cutting the resolution to 800x600 and see if your results improve.

    Another thing to try would be toggling the "vertical sync" option in your video card's advanced properties. This option specifies whether your video card synchronizes frames with the monitor's refresh. Your CRT probably refreshed at 100Hz, and your LCD is probably just 60Hz, so vertical sync could be slowing you down even if you haven't increased your display resolution.
  • Translation. . . (Score:4, Informative)

    by Fantastic Lad ( 198284 ) on Monday September 27, 2004 @10:31AM (#10362851)
    When I got my flatscreen, (A Samsung Syncmaster 570V - A fine piece of no-lag hardware), I was curious about how the thing worked.

    So, of course, it got opened.

    Specifically, I was curious about the fact that I was able to plug the thing directly into my (very) old graphics card which was built before there were such things as desk top flat screens, and actually have it work.

    The signal being output by a graphics card is designed to be understandable by the average computer CRT. --Which, (when I've opened those in the past), don't contain a whole lot of extra electronics beyond on-off switches and very basic control systems. That is, with a standard CRT, the signal from the graphics card in my compy pretty much feeds directly into the electron gun and magnetics control system of the CRT monitor with very little intermediary electronics in between. All the really clever electronics is done by the graphics card back in the tower case.

    So. . .

    Since TFT monitors work on a radically different principal than CRT technology, this means that the output signal from my old graphics card, (which I'm guessing is analog), must be translated into a very different type of signal which can be interpreted by the TFT screen electronics, which I am guessing is a digital signal.

    This would mean. . .

    The original image dreamed up by the computer is digital, then converted to analog by the graphics card so that the CRT can apply it, and then because there is no CRT, it is converted back again into a digital signal for the TFT.

    Oh yeah. Now that's efficiency!

    And it worried me, actually. When I was shopping for my flatscreen, I was bugging sales people, "So are you SURE I don't need some kind of proprietary graphics card to run this thing? If that's the case, then I'm no going to get a flatscreen. I need a GOOD graphics card. Not some hunk of standardized junk made by the flatscreen manufacturer!"

    The sales guys always just shook their heads. "No sir. You just plug it in."

    "Oh. . ." I wasn't feeling very reassured.

    But what do you know? I plugged it in, and no problem. It worked like a charm. So, like I said, I had to open it up.

    When unscrewed and pulled apart, voila! Unlike the guts of a standard CRT, there before me inisde the TFT was a whole LOT of extra circuit board and chip set confusion sitting between the monitor cable plug and the flexi-cable which feeds into the actual screen system. So there is some serious signal in interpretation going on! --And none of it, I imagine, would be industry standard; each CRT to TFT signal converter is probably designed and built by whoever happens to be making the flatscreen. This extra engineering necessity provides a whole pile of room to make bad decisions and crappy electronics.

    My guess is that this is where the lag you are experiencing is coming from.

    For my part, I was fortunate in that Samsung did the job well. I ended up with a system which works invisibly, with no perceivable lag between any input and screen output. Perhaps you can sell your screen off on Ebay and get a better monitor.

    Of course, the problem may be something else entirely, but that's my two cents. Hope it helped!


    -FL

Adding features does not necessarily increase functionality -- it just makes the manuals thicker.

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