It is slightly slower if compiled for 1.1. We are trying to optimize it, the only other solution is to release an application for 1.3 cards alone.

gdf

Can't BOINC server be set to send separate apps based on compute ability? If not and if there's only a slight difference I'd vote for the one most compatible with all cards. Another option would be differently compiled optimized apps available to install via an app_info.xml.

Hi SK,

I'm not saying your factor of 1.4 is wrong. In fact, I couldn't even if I wanted to ;)

The point is that I don't have a "better" number. Just the gut feeling that in typical games the speed up will be lower, because otherwise GT200 would have been quite unbalanced in some way. However, if any of the shiny new features can be used, the speed up can be much larger. At Milkyway I'd expect a factor of 8 per clock due to the massive increase of raw DP number crunching power.

Regarding a speed up of 1.4 for GPU-Grid. Well, I wouldn't be surprised if GPU-Grid could make good use of the new features. But deciding for a specific number would be too bold..

Regarding the memory bandwidth: on GT200 the GDDR3 is used between 1000 and 1250 MHz (data rate = frequency * 2) whereas current GDDR5 reaches up to 1200 MHz (data rate = frequency * 4). That's a nice speed up of 2 due to the frequency. Overall bandwidth should be 1.5 times higher than on GT200 (512 vs 386 bit). To sustain 2x the performance one needs to first approximation 2x the bandwidth - So we're not winning much here.
However, as you also said, the on chip cache is better and larger now. And GT200 wasn't terribly bandwidth constrained. That's why I think we're not winning much here, but the memory subsystem should still be fast enough.

I like the sound of your little GF100.

Me too :D
I just hope nVidia doesn't do it the GT200-way: don't release a mainstream version of the fat "flag-chip" at all. They've done quite some dodgy moves in the past (just remember the endless renaming) .. but I don't think they're stupid or suicidal!

Best regards,
MrS

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Scanning for our furry friends since Jan 2002