AMD Unveils the Liquid-Cooled, Dual-GPU Radeon R9 295X2 At $1,500

wesbascas (2475022) writes "This morning, AMD unveiled its latest flagship graphics board: the $1,500, liquid-cooled, dual-GPU Radeon R9 295X2. With a pair of Hawaii GPUs that power the company's top-end single-GPU Radeon R9 290X, the new board is sure to make waves at price points that Nvidia currently dominates. In gaming benchmarks, the R9 295X2 performs pretty much in line with a pair of R9 290X cards in CrossFire. However, the R9 295X2 uses specially-binned GPUs which enable the card to run with less power than a duo of the single-GPU cards. Plus, thanks to the closed-loop liquid cooler, the R9 295X doesn't succumb to the nasty throttling issues present on the R9 290X, nor its noisy solution."

Re:here's how stupid this is

[fuzzyfuzzyfungus]

Thermal conductivity of water: approx 0.58 Thermal conductivity of copper: approx 401 The only reason to have water cooling in anything is to brag to your friends that you have water cooling. In reality, metal cooling works better.

The water (.58) replaces the air (.024) in the cooling setup, not the metal. Watercooling systems tend to have markedly smaller heatsinks, since they just don't need the same surface area(at the low end, just a copper plate with a flow chamber on top of it, some more complex designs use something more or less similar to a small air-cooled heatsink; but sealed for water to flow through.

Now, I think that there have been a few nutty-and-exotic liquid-metal cooling systems; but those are hampered by the fact that they just aren't better-enough than water for the money (the delta T of the CPU's package and the waterblock is still the same), pumping the (substantially denser) liquid metal is more energy intensive, and most candidates are either unpleasant or expensive, or both.

If you want something that won't go all hazmat on you if the system leaks; but won't harden in the cooler parts of the loop, 'Galinstan' is probably the best bet; but you sure don't make things cheap by making them ~ 20% indium.

If you are...aggressively risk tolerant... a nice Cesium/Potassium/Sodium alloy will stay liquid to almost -80 (celsius); but, um, not a good plan, OK. Straight Mercury works fine down to almost -60; but that stuff is dense and not particularly pleasant(plus, it amalgamates with a number of metals quite readily. You did check your waterblock, radiator, pump, and all other contact surfaces for compatibility, right?). If you aren't the kind of coward whose dishonor makes him cry about things like "my cooling system catching fire on exposure to air or water vapor", NaK is a lovely coolant.

Basically, for something that is such a pain in the ass, you'd better be getting results substantially superior to normal air or water cooling, which you'll only get with active heat pumps that can actually pull the CPU below room temperature. At that point, the rather low freezing points of any available metal alloy become an insurmountable problem. Other materials don't have quite the same thermal conductivity; but they'll be happy enough keeping things well below the -100.

13 watts at idle is better than I expected

[Dr. Spork]

So finally, AMD came out with a power algorithm that reduces power consumption when the resources of the GPU aren't needed. I'm not sure where in their product line they introduced it, but it's about damn time. There are all kinds of good reasons to leave our computers on all the time, but I haven't been doing it because the idle power consumption has been needlessly high - in my case, over 50 watts. This adds up over time. Just how much power does a high-end computer need to idle, serve files, run non-demanding background processes, etc.? Millions of computers do just that, for many hours every day. A focus on reducing the power draw of these basically idling computers could make a huge difference to the world.