No unfortunately there is more to it than that! First there is the brand of gpu you get, as SekeRob said most new ones are OpenCL compatible but not all are, older ones can be hit and miss. Go to the Nvidia or AMD website and look at each cards specs before you buy if you can't find it! Second heat is a killer of pc's and gpu's put out a TON of extra heat that basic box pc's just can't handle very well. When Dell/HP/whoever makes a pc they do not expect the gpu to be used for crunching, so they build a box for the average user and it works fine for the most part, but when you start crunching you are going into the realm of 'geeks' and that is not what they think of as 'normal' users. We are more in the 'gamer' area of their thinking. Adding better/more fans might fix that, a better case WILL, but so could just leaving the side off of it. But then leaving the side off of a pc is ugly, so if yours is in the Living Room that may not be the best idea. Third gpu's use power, lots of power, most basic box pc's are built to make money for the vendor, that often means using bare bones parts that are good for what they do but not always for 'geeks'. So that is probably another expense you will have, upgrading the power supply, which really is normally just plug and play. Fourth all those extra workunits will require more on board memory, ram, which could mean a ram upgrade for the machine, meaning even more expense. Fifth your electricity costs WILL go up if you use a gpu to crunch with! Making the decision to go to gpu crunching should NOT be taken lightly, but once you go you will NEVER go back to just plain old cpu crunching!! It is kind of like dial-up, once you try cable you will NEVER go back to dial-up again!!! I have a 6 core AMD machine crunching for WCG, it is doing a little over 3,000 RAC using all 6 cores of the cpu crunching for SN2S, I also have 2 gpu's in the same machine and together they are getting OVER 320,000 RAC on their project!! And the gpu's are NOT the newest by any means!!

I haven't seen a comment about it yet, but I presume the time calculation for badges will be the same for GPU as it is for CPU: 24 hours of GPU crunching = 24 hours of CPU crunching. Not that I'm concerned about badges and points, just curious.

FWIW I have done some experimenting getting ready for the WCG GPU app by running a few other GPU projects. One thing you can do to save power and reduce heat is to down clock the memory on your graphics card. The default memory setting on the ATI 5830 I'm running is 1000MHz. My final setting was 300MHz. with no discernable loss of effeciency. It lowered the power consumption by 25 watts and temps by 10c when running POEM. It will be interesting to see what the comparisons will be when WCG/GPU goes live.

what WCG projects use gpu at this time?

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