Is Prescott 64-bit? 487
unassimilatible writes "According to The Inquirer, Intel's new Prescott has 64 bit instructions lurking inside. Could really rain on the parade of those who thought the new Athlon 64's would be supreme - especially when you look at Intel's price roadmap. Don't run out and buy an Athlon 64 just yet..."
Hrmm (Score:5, Funny)
Comment removed (Score:4, Insightful)
Re:Hrmm (Score:5, Funny)
An Easy Bake Oven uses a 100W incadescent light bulb as the heating element. So with a heatsink and a fan, does that make a case with Prescott Inside an Easy Bake Convection Oven?
Re:Hrmm (Score:3, Informative)
http://www.theinquirer.net/?article=11588
-Charlie
Re:Hrmm (Score:3, Funny)
16bit? (Score:3, Funny)
FUD (Score:4, Insightful)
Re:FUD (Score:5, Interesting)
In the 90s Intel did the same with the Pentium and the R4000s that were going to be the basis for the ARC platform. Intel said that the Pentium was going to be out any day then and it was going to run circles around the RISC machines. The pentium was at least 4 years late and was well behind RISC offerings in performance. But Intel managed to kill the ARC consortium.
This is the latest in Intels FUD campaign, maybe it is time to break the circle... buy intel and have 64bits TODAY... screw them, with their "ooooh we may have a surprise for you" and all that nonsense.
Re:FUD (Score:3, Funny)
you did mean AMD, didn't you? or maybe intel's marketing is so good that it made you change your mind halfway through your post
Itanium? (Score:3, Insightful)
Itanium is a late-comer to the nonx86 64 bit club (PowerPC, Power, SPARC, SPARC compats (PRIMEPOWER), MIPS, Alpha).
I can see why one would pick Opteron over the others ev
Re:Itanium? (Score:3, Insightful)
Given the architectural advances inherent in the Itanium's design, I sincerely hope it wins out in the desktop arena when that battle is played out. With AMD releasing their x86-64 CPU's, I imagine this battle will become much more center stage, and maybe we'll see the Itanium (or a desktop variant) seeing some huge price drops sooner rather than
Re:FUD (Score:3, Insightful)
Well, maybe he's proving your point with his Ford analogy, even though he doesn't realize it. Ford may have been the biggest car manufacturer at one point, the leader, the only choice. But times change, and like you said, there's true competition and choice now in the car market.
Let us hope that Intel's "Ford years" are nearing an end as well.
It would almost have to follow AMD's conventions (Score:5, Interesting)
Intel is an AMD64 licensee (Score:3, Interesting)
My bet is that Intel won't go anywhere near 64bit on the desktop for a very long time (like never). We will see dual (or more) cores before that ever happens (which is slated for '05).
amd64 CPU's available _now_ (Score:5, Informative)
With other groups like the Debian project well underway in their amd64 porting efforts, you can expect thousands of popular applications built for the amd64 platform. There's tons of software available for amd64 already, and you can bet by the time that AMD releases their "Athlon64" or whatever they're targeting the low-end market with, there will be even more.
The tide is turning for AMD (Score:5, Insightful)
Great!! (Score:4, Funny)
Uhm... Maybe I'll buy it and install linux on it, all the big good games are coming to linux now it seems
Doubt that I will totally be rid of windows in the next few years though. You know. Work and such
Let me see if i can understand this (Score:5, Interesting)
So it seems to me that possibly Intel are waiting to see how AMD's 64 bit chip goes, and if its going better as a 32/64 bit chip then Intel's Itanium, release their Prescott with "fully" added 64 bit functionality?
Am i correct in my logic? I can't really follow why they're keeping tight about it.
Re:Let me see if i can understand this (Score:4, Insightful)
Re:Let me see if i can understand this (Score:4, Funny)
Re:Let me see if i can understand this (Score:2)
IInntteerreessttiinng (Score:5, Funny)
Re:IInntteerreessttiinng (Score:5, Informative)
Re:IInntteerreessttiinng (Score:5, Funny)
Wow! Not. (Score:5, Insightful)
Hey! There's a rumour that Intel might have not bothered marketing their new developments properly. You should ignore what is on the market and working just in case you can tweak a future chip to get something a bit like it. You heard it here first!!!
Idiot.
This is pure speculation (Score:5, Insightful)
The allegedly informative statement is couched in so many conditionals that they of course can once again squirm their way out of any uncomfortable spot they might get stuck in.
Plus, I don't see Microsoft supporting not one but TWO Intel-specific 64-bit platforms.
Hold on to your Athlon64 pre-orders, boys and girls.
Re:This is pure speculation (Score:2)
If the platforms both become popular they will. Having
No, it isn't (Score:5, Informative)
-Charlie
The Inq (Score:3, Insightful)
Re:This is pure speculation (Score:3, Insightful)
Especially when it comes to info technology.
They often get the scoop on things well before anyone else does. It's useful to know about things before they happen.
I've never bought Intel (Score:5, Interesting)
My biggest problem is what to do with the old mobos and processors that I put aside due to upgrading.
No, I've never had a reason to spend more for so little (it's even arguable whether you get more for spending more
Re:I've never bought Intel (Score:2)
Finally caught on? (Score:5, Insightful)
And even if that does pan out it's highly unlikley to appear in desktop Prescott core chips anytime soon. Seems much more like something you'd find in Xeon MPs and later DPs to eliminate the need for that hack they call PAE.
Though i hardly see how 'somebody told us a seinor exec said' makes Slashdot.' (I understand that's what the Inquirier bases most of their news on, i thought we had slightly higher standards of reliability)
There is another Chip-Architect article (Score:2)
-Charlie
There's more to it than 64-bit instructions (Score:5, Interesting)
Re:There's more to it than 64-bit instructions (Score:4, Informative)
Intel doesn't do on-board memory controllers because they got burned by Timna.
Performance doesn't come directly from 64 bits (Score:5, Informative)
Itanium is a full fix to the problem. The horrendous x86 ISA is completely replaced by an explicitly-parallel (EPIC) instruction set that has all the nice properties of a RISC machine (easier to compile for, less stress on the memory system as you get 128 registers, easier for the machine to decode the instructions as they're fix format and don't require RISC conversion, etc.). The problems with it are:
1. You need a compiler that "knows" how to bundle instructions effectively (a VLIW-compiler). GCC clearly isn't there yet (it's not uncommon for the intel compiler to beat gcc by 30->50% when running computationally-intensive stuff)
2. Being completely different than x86, it can't be very efficient at emulating x86 programs.
AMD partially fixes the problem by extending the x86 ISA to 64 bits, *and* adding 8 general purpose registers. Because they just extended the ISA, running old code is just as fast. Furthermore, new code can benefit from from the extra 8 registers, and run even faster.
For the short term the Opteron is a pretty impressive chip, but I really don't see how AMD is going to stay on Moore's curve with such a shitty instruction set architecture.
P.S. Clearly 32 bits can only address 4GB of RAM, and for *some* servers more addressing space buys you something. But I'd say they are a very small minority.
Re:Performance doesn't come directly from 64 bits (Score:2)
Re:Performance doesn't come directly from 64 bits (Score:5, Informative)
Now, I admit I haven't spent a lot of time looking through my x86-64 manuals, because it's been vaporware until fairly recently, and furthermore they lied to us about how many HT buses would be on each flavor of processor right up until the very end, so I won't be buying anything until either they bring out an Athlon 64 MP which has the missing hypertransport bus re-added, or until the Athlon 64 brings down the price of Opteron processors. My Athlon XP is holding me for the time being, and besides, there's no 64 bit windows yet. Even after there IS a 64 bit windows, I expect to have to wait a little while for some of my drivers. So it hasn't really been a serious consideration for me. But I suspect that in many cases they have provided us with new instructions to replace the old instructions which require that the result go into specific registers.
So, x86-64 has 16 GPRs, plus 16 "XMM" registers for SSE/SSE2, not to mention it implements the SSE2 functions from the P4. I think it pretty effectively does all the things it needs to do. Meanwhile it still has hardware solutions for emulating all the deficiencies of the x86 so that it can maintain backwards compatibility without sloowowwwwwing dooowowwwnnnn like itanic. It's the perfect solution for those persons who are not ready to give up their backwards compatibility, and it does not have the flaws that you and vlad assert. If you don't believe me, go root around AMD's site for the PDFs. Hell, I even got them to send me the paper documentation for free, which I intended to read in the bathroom. Unfortunately, even my wholly irrelevant nintendo summer 2003 catalog has been water damaged in there, so I'm definitely not going to venture into the latrine with my AMD technical docs.
Re:Performance doesn't come directly from 64 bits (Score:2, Informative)
Intel has had more than 32 bit addressing since the Pentium Pro, which introduced 36 bit physical addresses (64 GB).
Re:Performance doesn't come directly from 64 bits (Score:3, Informative)
Re:Performance doesn't come directly from 64 bits (Score:2)
Re:Performance doesn't come directly from 64 bits (Score:3, Funny)
Re:Performance doesn't come directly from 64 bits (Score:2)
Look to the G5 (Score:3, Informative)
As for AMD, you can see the effect by running a program in 32 bit mode, then running a 32 bit program recompiled to take advantage of the registers in 'compatibility' mode. There is quite a differe
Re:Performance doesn't come directly from 64 bits (Score:5, Informative)
The Itanium ISA is elegant an and clean in some places but in others is an ungodly mess of complicated things. Take the register save engine (RSE) for example. It's supposed to handle spilling registers to the stack and loading them to the stack. This includes handling page faults, exceptions, interrupts, and memory errors. Oh yeah, this is supposed to be automatic and handled invisibly by hardware without software intervention. Hasn't happened yet.
Also the EPIC ISA that the Itanium uses isn't easy to compile for. This is one of the biggest problems with the Itanium. It requires compilers to pull out a lot of parallelism in the code and present that to the hardware for execution. Intel sort of glossed over this when introducing the Itanium about 10 years ago and the compiler technology hasn't been able to really do this. So although the Intel compiler is better than gcc, it still isn't all that great.
Incidentally, the Itanium does a better job at emulating the x86 ISA in software than in hardware. It was a big deal a few months ago when Intel introduced a software x86 emulator that offered a dramatic improvement over using the built in hardware emulation.
Compiler (Score:3, Informative)
I also agre
You know you're in trouble... (Score:2, Funny)
FUD! (Score:5, Insightful)
Re:FUD! (Score:5, Insightful)
Erm... (Score:2)
Re:FUD! (Score:2)
There's that multi-billion dollar investment in Itanium to think about not to mention the partneships Intel has tried to build around the chip.
This is all about the server market. Itanium is expensive because it requires all new software. It's performance has been disappointing too. That has recently improved, they actually beat Opteron in the tests I've seen on 64-bit code. But Opteron's value propos
Re:FUD! (Score:2)
I'm not going to debate whether or not Prescott has 64-bit extensions, but assuming it does, and knowing that AMD thinks they have a sure thing, would YOU galavant about like a some idiot who arrived late at a party saying "lo
Good point, one little problem. (Score:5, Informative)
For about 3 months, I have known there was 64 bit functionality there, but I didn't have enough to prove it to my own satisfaction. I chased leads, interviewed people, and got that info.
The fact that IDF brought me into close proximity with a ton of sources was the thing that got me so much info so quickly. There was only one thing from Intel directly, the rest were from third parties supporting the chip. If IDF had happened last January, I probably would have gotten the info then.
-Charlie
Is Prescott 64-bit? (Score:5, Funny)
I've Heard This Before (Score:5, Insightful)
If Athlon 64 doesn't take off, Intel could keep things bottled up untill needed, or even nerver turn it on, letting consumers get 64 bit computing in a future chip that they've had time to improve the instruction set on or something.
It really is an interesting idea, and quite a consipracy theory. Is it true? Who knows! But with all the hub-bub around the Opteron and the upcomming Athlon 64, I wouldn't be suprised if Intel were to drop a bomb like this soon. Just think. Intel first steals AMD's thunder by anouncing the P4EE. Not only is it announced first, but it trounces the competition in benchmarks (this is speculation, I haven't seen any numbers). If the P4EE is fast enough in benchmarks and the price is competitive with the Athlon 64, AMD could be in some trouble. Now if in a few months, Intel announces something like this, AMD's savior that they seem to be betting the farm on could be in BIG TROUBLE. If this happens, AMD's best hope is that Intel DOES use their instruction set, because if they don't things could get very ugly.
So will any of this happen? Who knows! But that can't stop me from speculating! There is one last thing I'll comment on. If Intel does release a 64 bit processor soon, and doesn't use AMD's instruction set, there is a small possiblity that THEY (Intel) could be in trouble if the Athlon 64 (and friends) make a big enough splash. They might come too late to the party to make big decisions (like which instruction set rules).
These things seem a bit more likely, given that Intel seems to be in trouble right now (IMHO). While they are ratcheting up the P4 fast, the fact is that they weren't planning on 64 bits any time soon, AMD has forced the issue on them. If AMD is right, that will put them in trouble. And anyone who follows this kind of stuff knows that Intel has some major heat issues. Current opterons put out what, 70 watts? And some of Intel's upcomming chips are looking at 120 watts during usage (maybe as high as 150 under full load). Between heat, stagnation, and pathetic sales of the Itanic, Intel seems to be in Trouble.
The last thing that I'll say is a message to Intel: when you move to 64 bits (or even if you are just going to stick with 32 for a long time more)... DROP THE NAME PENTIUM. I'm tired of it. There have been FOUR of them (not counting all the different core revisions of each one). I know you have marketed that name for years, but it's time to move on. When will it stop? The Pentium 5, which you might call the Pentium Pentium, or Pentium Squared? Will I have to wait untill the Pentium 17 before you get a new name? Come one guys. Time for a name change.
Re:I've Heard This Before (Score:5, Insightful)
You've got to be kidding. It takes years to develop a compiler for a new instruction set. If Intel suddenly announced that a lot of their chips were 64-bit capable, it would be completely useless, because there would be no software at all that could take advantage of it.
Keep in mind that running 64-bit programs requires that the Operating System supports the instruction set completely (otherwise the registers wouldn't be saved properly, at a minimum), so they'd basically have to have Microsoft on board, in addition to probably a Linux port in order for it to be useful.
And in the meantime, all of those extra instruction decoders and extra registers would be there on the chip, wasting valuable silicon that could be used for a larger cache. No way - Intel wouldn't sacrifice potential speed now for the chance to surprise everyone with a 64-bit processor later.
Face it: Intel gambled with the Itanium, and so far their gamble hasn't been paying off. It's far too early to see who will win in the long term, but it's clear that the Itanium hasn't been an overwhelming success, while the Opteron is definitely equally popular already, if not already more popular.
Re:I've Heard This Before (Score:2)
64-bit (Score:5, Interesting)
Isn't this what Intel wants? (Score:5, Insightful)
WTF? (Score:2, Insightful)
"reporter" pull his news from?
In honor of my first computer... (Score:4, Funny)
AMD should kick it Old School.
Has anyone Considered? (Score:5, Insightful)
Pah. (Score:4, Insightful)
I knew you could!
PreSCOtt (Score:5, Funny)
In other news, SCO sues Intel for the use of their na... SLLLLLLLAAAAAAPPP!!!
Ouch, that hurt!
this scares me (Score:3, Interesting)
does this mean the chip will be tailored for the MS OS?
will it be totally worthless if you buy a system and load a different OS?
64 bit doesn't matter YET (Score:3, Insightful)
Buying a cpu for applications more than 3ish months away is a foolish decision. The price and product cycles makes buying those capabilities ahead of time a bad idea. You only have to look back at the early pentium adopters to realize what a little patience can do for you. Back then, a fast 486 would hands-down beat a pentium in any application except for a couple of image editing apps, and things stayed that way for months. Things stayed that way for nearly a year until Intel nearly doubled the speed of the pentium, finally putting the 486 out of the picture. A 64 bit processor better be damn fast today or it shouldn't be purchased. By the time the extra performance seen from 64 bit apps and operating systems is realized, you'll be able to buy an even faster/newer cpu for less money. Save your pennies and get what works the best today.
For what it's worth, TODAY the fastest cpu seems to be an Athlon64 or Opteron. Hidden 64 bit instructions won't change that a bit. Show me the application benchmarks and I'll believe. Until then, I'm saving my coin for the next upgrade cycle.
Comparison with Apple's G5 (Score:3, Interesting)
I'm glad to see someone finally point this out. The exact wattage number is 46.7 watts for the 2 GHz PowerPC 970 "G5" running at full speed (2GHz CPU and a 2:1 multipler for a 1 GHz FSB).
A 2.4 GHz P4 (400 MHz FSB) uses 62 watts, newer P4s use even more. Prescott is expected to use 100 - 105 watts. (And this is totally ignoring the even further power needs of the "extreme" edition with its added transistors for on-die L3 cache)
Apple has always seemed to overengineer the heatsinks and fans in their desktop model, for about as long as I can remember. Oddly, many of the PowerBooks use a much different "transfer the heat from the CPU, Chipset, and GPU right to the bottom of the case" cooling method.
Actually, do go get that AMD or IBM chip (Score:3, Informative)
Don't run out and buy an Athlon 64 just yet...
To anyone that 64 bits might make a difference for, they're steering clear of Intel, who has stated [com.com] they're not going to focus on that desktop market for another 5 years. So all this article amounts to is Prescott FUD to support Intel's (misguided) roadmap.
Disclaimer: I own some AMD stock and I do my Unix development on Mac OS X.
"Don't run out and buy an Athlon 64 just yet..." (Score:4, Insightful)
I'm afraid this line of reasoning just doesn't cut it.
Intel does not want a 64bit x86 on the market. They want to lead everyone to Itanium where they don't have those pesky AMD guys competing with them.
It's for this precise reason that everyone SHOULD run out and buy an Athlon64. If nobody buys them, Intel will have no reason to jump into the 64bit x86 market at all.
I for one can't wait for Athlon 64 to hit the market... I need a viable 64bit Linux workstation solution and I need it yesterday.
-cjs
Re:"Don't run out and buy an Athlon 64 just yet... (Score:4, Interesting)
Re:"Don't run out and buy an Athlon 64 just yet... (Score:3, Interesting)
It's not such a big deal with open source software, but check out the price/performance of x86 desktop hardware and peripherals some time.
Re:"Don't run out and buy an Athlon 64 just yet... (Score:4, Interesting)
I don't know exactly what you mean by your last comment. I don't really know of any x86 specific hardware or peripherals except for the MBs and CPUs. Just about every other peripheral or piece of hardware will plug in to many Alphas and any recent Mac (drivers and firmware aside).
I've used many video and network cards off-the-shelf as well as standard RAM in my Alpha and use standard "PC" memory, drives and peripherals on my 5 year old Mac.
I have checked out x86 price/performance. It's not been enough to get me to purchase any of it. I get more real work done on my Mac per dollar than on x86 (no virus downtime, few system updates, etc), and my Alphas put out more heat per dollar than any x86 could in it's wet dreams.
this is a (supposed) underdog competition (Score:3, Insightful)
x86 has been 48-bit for years (Score:3, Informative)
64bit isn't a panacea... (Score:3, Insightful)
Fud, FUD FUD!!! (Score:3, Insightful)
So, here we have Itanium that isn't doing well on the market, porting to it's 64 bit ISA is hary and which performs legacy code horribly. No, really horribly.
And then here we have Athlon 64, which is cheaper than Itanium, requires very little porting to 64 bit code and which performs legacy code fantasticly - in fact, it's so good that you might consider and Athlon 64 just to run your legacy x86 code, 'coz it's so fast.
So what does Intel do? Float a flaming horseshit of FUD about Prescott being somewhat 64 bit - but hey, Intel didn't say it, the source was, uh, the Inquirer, for cryin' out loud!
Well, until someone doesn't put the Prescott under an electronic microscope and makes their conclusions based on hard facts, and concludes that, indeed, The Inquirer is right, I say FUD and double FUD from a company that is known to engage in it!
Old Labour... (Score:3, Funny)
Is Prescott 64 yet?
Re:I wouldn't buy the Athlon anyway (Score:2)
I would... (Score:5, Insightful)
My 450MHz AMD K6-2 worked fine, at 4.5x100MHz, my 1.2GHz Athlon Thunderbird worked fine, and my Athlon XP2400+ (2.055 GHz after some interesting bus overclocking) works just fine.
I've never had a problem with them. Do you know what you're doing? Setting the voltage levels is required on the older boards, and that actually means reading the provided motherboard manual.
I'm looking forward to a dual-AMD 64 bit configuration for home at some point, it looks pretty sweet.
Re:I wouldn't buy the Athlon anyway (Score:4, Insightful)
Yes. Both my machine at work and at home are dual Athlons. Not only do they work great, but they also were very good price wise. On top of that, Lightwave (3d Rendering App) competes very nicely with the P4s, though LW is heavily optimized for Intel.
I'm not an AMD zealot, but I guarantee you that if I had the problems you did, my AMD'd be in the trashcan in a heartbeat. I can't afford aborted renderings.
Re:I wouldn't buy the Athlon anyway (Score:2)
Re:I wouldn't buy the Athlon anyway (Score:2, Insightful)
Re:I wouldn't buy the Athlon anyway (Score:2)
Re:I wouldn't buy the Athlon anyway (Score:4, Informative)
AFAIK, other than stomping on occasional driver bugs, Athlon chips have been pretty excellent ever since. I have an Athlon 1900+ on an ASUS A7V333 that's rock solid, and a new Athlon 2500+ on an Nforce2 board that's not quite as solid, but which is still pretty good.
I'd like to see some improvements on the NForce2 chip stability. It's not all the way there yet, in my opinion. But the VIA chipsets are extremely solid.
Re:I wouldn't buy the Athlon anyway (Score:2)
Re:I wouldn't buy the Athlon anyway (Score:4, Interesting)
Well, I've got the old K5PR133 sitting on a shelf now that did years of sterling service, first as my main desktop CPU, then moving back to the firewall CPU, until it got replaced by the K6 II 350 (which is still in the firewall machine, and has been there, running solidly, day in, day out since about 1999, and was my desktop CPU before that,replacing the K5).
Replaced the K6 II with an Athlon 700 (original slot A). That ran fine, until the board fritzed, due to the old capacitor problem that ran rampant in late 99, early 2000.. The board lasted until 2002. The only reason it's not in the firewall box now is that I can't get another board for less than it'd cost to put a faster athlon in a cheap board..
The 2002 set I bought was a nice Athlon 1700 in an Abit board. Ran stably and never a problem.. That's now in the girlfriend's machine (built one for her from the last generation of hardware I had lurking), and now I'm using an NForce2 board with an Athlon 2500 (Barton core).
No problems with any of them.
If the college computer broke, are you sure it's the CPU? Not memory, motherboard, power supply or any of a myriad of other issues?
For the laptop, is it a problem with the manufacturers not putting good cooling and airflow in the laptop (or, heaven forbid, a desktop CPU in a laptop case to save money/add a little extra speed)?
By all means, stick with Intel if it keeps you happy, but I've had a long history of using AMD chips, and I like 'em. If I saw a reason to use Intel's chips, I would.. I just never have to date...
Re:I wouldn't buy the Athlon anyway (Score:3, Informative)
Tell me, Amsterdam Vallon, what broke on your AMD college computer? Unless it was a defect with the construction of an AMD processor, your point will prove irrelevant. I'm using an AMD processor right now, and my Windows 2000 machine got a virus thanks to IE and broke. That's not AMDs fault. My old motherboard needed a flash
Re:I wouldn't buy the Athlon anyway (Score:4, Insightful)
Dell - Notebook
HPAQ - Notebook
Alienware - mobile gaming
VoodooPC- mobile
They don't call em laptops anymore because, as you've noticed, they often don't work well in your lap
Re:gotta compete (Score:3, Insightful)
Look at the Apple Macintosh. The platform is completely proprietary, and controlled by Apple. Apple successfully switched architectures in the mid-90s, from the CISC 68000 to the PowerPC. These architectures were completely incompatible at the machine code level. But since no one was selling souped-up knockoff 68000 Mac clones in competit
Re:gotta compete (Score:4, Informative)
You do realize that there has been no such thing as a "CISC processor" since the Pentium Pro came out. Underneath the X86 bytecode VM, Pentium IVs, Athlons, etc. are highly advanced RISC cores with multiple concurrent execution units.
The main reason that the huge expensive power sucking Itanium scrapes out a small lead in benchmarks over X86 CPUs is because of its expensive huge power sucking cache.
Re:gotta compete (Score:2, Interesting)
But the instruction set still hobbles the design in many ways. The logic to convert x86 instructions to micro-ops takes up space on the die and uses extra power. And any way you look at it, you have to read from memory a lot more often with 8 "general purpose" registers than 32 real GPRs, which is what most sane CPUs have. Itanium doesn't have to do this, PowerPC doesn't hav
Re:gotta compete (Score:4, Informative)
However, the compact legacy CISC instruction set does conserve on instruction cache space. This offsets much of the cost of the conversion logic. Moreover, it allows custom optimizations for the exact architecture du jour without affecting binary compatibility.
And any way you look at it, you have to read from memory a lot more often with 8 "general purpose" registers than 32 real GPRs, which is what most sane CPUs have.
Many modern X86 CPUs have more than 32 real GPRs which are utilized by register renaming. Like quantum mechanics, the processor state for any given instruction is smeared out over time and space, and the CPU is operating on many instructions simultaneously. The number of visible registers just doesn't matter as much as it would seem on the surface.
Itanium doesn't have to do this, PowerPC doesn't have to do this, no modern ISA requires this nonsense.
They will when somebody figures out the next architecture trick that doesn't match the assumption of the designers of their ISAs. Take a look at history; remember when MIPS stood for "Microprocessor Without Interlocked Pipeline Stages"? What did the R4000 introduce? Could it be - interlocked pipeline stages? Exposing CPU implementation details to the software is not something that wears well over time.
It doesn't just "scrape out a lead" in floating-point benchmarks, it absolutely destroys the x86 competition.
That's because the FPU has not been very important in the X86 market up to this point. Business and multimedia apps just don't need it. If AMD or Intel put their efforts into an X86 with ultimate FPU performance, it could match or beat the Itanium.
I suspect that Intel took advantage of the huge schedule delays in the Itanium to throw in more FPU horsepower because it had to beat the consumer-grade chips on something.
And oh yeah, its running at what, half the clockspeed of the P4? If Itanium had the same economies of scale behind it at this point, there would be no competition.
As I said, the cache and memory architecture is the primary factor in the performance of CPUs today. Clockspeed, instruction set, registers ... who cares? Everything that's not cache is only a small fraction of the die size.
All of that hardware architecture stuff is a red herring. Worrying about those non-issues has caused the Itanium schedule to slip nearly a decade while they desperately tried to write a C compiler that could statically wring out performance from their brittle concurrent execution model without the benefits of the run-time statistics information available to the X86 code translators.
Re:gotta compete (Score:4, Interesting)
And why isn't there an Itanium 2 or Power4 running at the same clockspeed as the P4? It's because they can't. To do more work per clock, they use more logic, and that takes more time. Don't you think that Intel would have a 3.2 GHz Itanium on the market now if it were technically feasible?
All of these CPUs use similar fabrication technology. This technology is capable of a certain number of fundamental logic operations per second per square millimeter. The P4 uses high clockspeeds only because it is marketed to users who think that MHz==performance. If marketing requirements were different, the P4 would have been designed to get the same performance out of 1/10th the clock speed with the same die size and the same manufacturing cost.
Stuck in the past?? (Score:3, Insightful)
Check out the price/performance of x86 some time. Also in many cases they don't even run much hotter or consume that much more power if you compare processors of similar performance.
The larva has evolved, grown wings and it flies. It's still an ugly bug, but it flies. And to the disgust of many chip architecture academics in their ivory towers, it flies faster than many supposedly elegantly designed RISC/postRISC bugs.
Heck, I hope the x86-64 becomes popular just
Re:gotta compete (Score:3, Informative)
LOL, Intel is actually their largest competitor. Every time they release a new chip guess who they are primarily up against? People who are running other Intel chips.
Without AMD though, I'm sure Intel would keep their new chips at higher price points for a bit longer and milk the power user crowd for a little more money.
Re:BAH! 286 is all you need. (Score:2)
Re:BAH! 286 is all you need. (Score:2, Informative)
You must be rich. (Score:2)
Re:Grrr... (Score:2)
Still no instruction reordering...