The important question is what proportion of machines actually have GPUs which can be used. Just because you have one doesn't mean that everyone does. Don't forget that it's not just older machines that don't, but huge, headless multi-processor servers. Unless/until a huge proportion of crunchers have such GPUs, it simply won't be worth the programmers' time to code for a minority of the population, especially when GPU coding is highly specialised and likely to be much more time-consuming than coding for the CPU. I would hope that the first thing WCG would do before embarking on such a venture would be to work out what proportion of the population of machines are even capable of running GPU progams.

No doubt there are lots of machines on WCG just sitting crunching in their spare time for months/years continuously. They are not necessarily running current operating systems (let alone current video cards). Let's take CUDA for example: It's only for WinXP onwards (no 2000 or Server 2003 support). I can't find anything which says it's been backported to 2.4 Linux kernels. How do you think WCG should handle that? Have multiple versions of the same project running at once for different releases of the same architecture?

Look how long it takes them to get a project running across just Windows and Linux and Macs right now. I believe you're looking at increasing that effort by an order of magnitude for an unknown return.

One important thing to remember about offering GPU versions of the applications is that it is not WCG people who program the applications, it is the scientists. WCG must accept and be ready to support GPU versions in addition to the others but they will not produce GPU enabled versions themselves.

WCG is interested in trying GPU versions and one of the current projects is interested in programming a GPU version. So there will probably be such a version in a currently-unpredictable number of months.

So let's just wait. Jean.

Just adding that I too am eagerly awaiting the day a GPU project is available on WCG. :) I have both ATI and nVidia cards ready to go. :)

Just some thoughts not necessarily in priority order ...

* The current BOINC Manager has some serious issues with regard to GPU computing. These involve the Resource Share model and work fetch policies that derive from that model.

* Heavy use of of the GPU can cause overheating in a system not properly set up. GPU use by a game is different than GPU use by BOINC.

* There are a few models of GPU cards that are usable as GPUs, however not all of them are suitable for all projects and this is unlikely to be properly addressed for some time (see above) for multiple GPU systems (where the GPUs are not matched and identical)

* SLI does not look to be supported at this time in that the GPU computing will only use the first GPU of SLI linked GPUs (I have not validated this, so cannot confirm).

* My GTX 280 preforms one GPU Grid task in about 4 to 6 hours (depending, they vary) The 9800 GT takes about 10-17 hours ... up to as long as 90 (not sure why I had the outliers but the tasks did validate).

* automatically "opting-in" of people could cause the project to damage a participant's computer. This is one case where the opt rule should be a manual choice.

* IN that so few projects use GPUs at this time it is unclear if BOINC Manager, even when fixed will properly manage these resources ... especially in a mixed environment (like if I put the 9800 GT back into the system that already has the GTX 280 like I had it before ... or if I buy a couple 9800's because I can get them for a lot less money ...

I have been looking for a Boinc project that supports ATI graphics cards. I see talk about NVIDIA’s CUDA on a couple projects sites, but no ATI cards.

I know the Lattice project is planning a GPU-accelerated version of GARLI for sometime in the future, but that probably would not support ATI cards when it starts maybe sometime down the road.

But it can be done, Folding@Home which is not a Boinc project has versions of software for ATI and NVIDIA graphics cards and a version for the PS3. I'm using my HD4850 graphics card for a Folding@Home project while I'm running my Boinc projects on my computer, if there was a Boinc project that would make use of my card I would use it there.