I’m just beginning to get my feet wet with HPC and am now at the stage where I’m about to buy a system.
I’m looking at a mobo with has 2 PCI-e 16x (2.0) slots. My thinking is that I’ll use one slot for regular video/graphics and the other for HPC. Does this even make sense? Can my CUDA system even be configured this way? BTW, is it possible to do some degree of HPC with even one graphics card?
I’m thinking about 2 8800GT or 8800GTS cards since the Tesla cards are priced too high for me.
I apologize if this has been discussed before. Please post your comments.
Yes, a pair of cards can certainly be used in this way. Note that you don’t have to dedicate a GPU just to CUDA. You can run CUDA programs just fine on the device that is also doing display, as long as each kernel call is less than 5 second long. (Longer than that, and the watchdog timer will kill your kernel so it can update the display.) This might be a good way to grow your system slowly as you discover how CUDA best works for you. The second card will only get cheaper with time. :)
Also, keep in mind that if/when you do get two cards, you can write multithreaded applications which use both cards at the same time. (One GPU per CPU thread) So if your plan is to use two cards at once, you also want to make sure you have a dual core CPU for best results.
The 8800 GT is a very nice card, I have to say. It’s cheap, has 112 stream processors at a reasonably high clock rate, and only takes up one card slot. After moving two 8800 GTX cards out of workstations which were too underpowered to drive them, we replaced them with 8800 GT cards. They are working great now, and, while not as fast as our GTX cards, they are at least competitive, and have the best “bang for the buck”. (Of course, sometimes you just want “bang,” and a more expensive card is a better choice.) The 512 MB models are best here. Only 256 MB limits what you can do, and two people have reported slow memory performance with the 1GB models in the forums.
The 8800 GTS (G92, don’t get the older one) looks like a fine card as well, though you’ve now jumped up to a double slot card.
Hopefully NVIDIA will keep a card like the 8800 GT in their product lineup as they expand the GeForce 9 to take over the GeForce 8 series.