Just as a heads up: stanford has been adding a couple of bigger WU's to the GPU2 client. ATi should be getting better points now, while nvidia might experience a little loss.
No worries for NV users though. There are optimizations for those GPUs coming
slegrand wrote:
No worries, there are plenty of NV optimizations in the pipe as well, but I need to validate them before turning them loose and right now, I'm swamped with some other F@H-related work. As things stand, the NV algorithm is more efficient but the ATI algorithm is simpler. Hence around lambda-sized molecules, ATI gets a perf spike while NV is still warming up and bogged down by the housekeeping incurred for its more efficient algorithm. For Fip35-sized molecules, NV is underutilized on GTX280, but ATI is doubly so on 4870 and that's why the perf differential there is just crazy.
In the long run in this GPU generation, I *expect* SP for SP that an NV GPU will be about 2.5x faster than an ATI SP. This is of course then modified by SP count and processor clock. If Mike finds a structural optimization to his code, then I will revisit that ratio, but that's my prediction for now. And the game resets with the next hw generation anyway so it's an ongoing arms race.
John Naylor wrote:
The work units have not been devalued, nor is there a motive to bring down NV points to make ATI and NV produce roughly equal points... Mike [Houston, the guy who builds the ATI cores] has a lot of optimisations on the backburner for his core while they sort out some obscure issue. If they wanted to level the production field, then those optimisations would probably be in already (from what I've read the problem is extremely obscure and not science related). The GPUs were always going to be used for bigger units, their enormous speed makes them inherently suitable for processing big systems, which can bog down the uniprocessor clients into multi-day units (e.g. p1487, which has taken a minimum of 4 days and a maximum of 11 days to fold on my system, and anywhere inbetween [that's not including downtime]). Both NV and ATI cards will be used to fold big units, but this was known from the start. It just seems that the ATI cards excel with these units where NV excels with smaller units. There is no intentional redistribution of PPD with these units.
Last edited by max (2008-09-08 15:20:08)
once upon a midnight dreary, while i pron surfed, weak and weary, over many a strange and spurious site of ' hot xxx galore'. While i clicked my fav'rite bookmark, suddenly there came a warning, and my heart was filled with mourning, mourning for my dear amour, " 'Tis not possible!", i muttered, " give me back my free hardcore!"..... quoth the server, 404.
