I have just bought a new PC with an NVidia GeForce GTX650 Ti video card.

I have an older PC with an NVidia GeForce GTX285 video card.

BOINC Manager reports the GFlops Peak value as 1586 for the GTX650 Ti and 1063 for the GTX285.

I have averaged the run times for the last 10 workunits for each card ...
GTX650 Ti - 24.7 minutes
GTX285 - 17.7 minutes

Does anyone have any ideas why the GTX650 Ti is taking longer to finish workunits than the GTX285 ?

I thought it should be faster.

I have just bought a new PC with an NVidia GeForce GTX650 Ti video card.

I have an older PC with an NVidia GeForce GTX285 video card.

BOINC Manager reports the GFlops Peak value as 1586 for the GTX650 Ti and 1063 for the GTX285.

I have averaged the run times for the last 10 workunits for each card ...
GTX650 Ti - 24.7 minutes
GTX285 - 17.7 minutes

Does anyone have any ideas why the GTX650 Ti is taking longer to finish workunits than the GTX285 ?

I thought it should be faster.

If you unhide your pc's we can look at what else is different to see if we can help figure it out.

Hi Mikey,

I've unhidden my PCs.

Daniel.

6xx cards has a horrible DP Performance to get user to buy there tesla cards..

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DSKAG Austria Research Team: http://www.research.dskag.at

I have just bought a new PC with an NVidia GeForce GTX650 Ti video card.

I have averaged the run times for the last 10 workunits for each card ...
GTX650 Ti - 24.7 minutes
GTX285 - 17.7 minutes

Does anyone have any ideas why the GTX650 Ti is taking longer to finish workunits than the GTX285 ?

I thought it should be faster.

The GFLOPS reported by BOINC is the single precision performance. You would see the 650 Ti faster on single precision projects such as Einstein. The DP performance on these cards is not so good. However the power requirements of the 650 Ti is considerably less than the 285. So even though the 650 Ti takes longer you are getting more performance per watt.

Joe

Thanks for your replies.

This explains what's going on.

Does anyone know if there is a website that lists the double precision performance of different graphics cards ?

It would be nice to know the DP performance of different cards so that next time I buy one I can pick one with better performance.

Best Regards,
Daniel

I've found the DP performance of the Radeon cards on the AMD website and I've found the DP performance of the Tesla cards on the Nvidia website, but so far I haven't found any figures for the Geforce cards.

Try these

http://en.wikipedia.org/wiki/Comparison_of_Nvidia_graphics_processing_units


http://en.wikipedia.org/wiki/Comparison_of_AMD_graphics_processing_units

I've looked at these pages already but I can't see where it mentions a Double Precision GFlops value for the Geforce cards.

I can only see Gflops or Gflops (FMA) and the GTX650 Ti has a higher number than the GTX285, so I think these must not be referring to the DP value.

Sorry, I've been on vacation. The double precision throughput of the NVidia 6xx series cards is 1/24 x the single precision.

You can see from the AMD tables on the 79xx series that they are 1/4 x single precision. This is why the AMD cards are much faster in DP. In single precision the NVidia cards and AMD cards are closely equivalent for the dollar, but in DP the AMD cards can be 6 times faster.

NVidia wants you to buy Tesla cards for several thousand dollars, but even these don't complete well on a cost basis with the AMD cards in DP. However, the Tesla cards do have lots of error checking and corrections built-in that make them more reliable for critical computations. These projects handle the reliability problems by sending out work units to multiple machines to verify results.

Joe

Thanks Joe, it all makes sense now.

I've just read that for the GTX285 the DP performance is only 1/12 that of the SP performance, this would explain why it is faster than the GTX650 Ti even though it has a slower SP performance.

I think I'll buy an AMD card next time.

Best Regards,
Daniel

Thanks Joe, it all makes sense now.

I've just read that for the GTX285 the DP performance is only 1/12 that of the SP performance, this would explain why it is faster than the GTX650 Ti even though it has a slower SP performance.

I think I'll buy an AMD card next time.

Best Regards,
Daniel

Other projects, like DistRTgen and PrimeGrid, LOVE the Nvidia cards MUCH more!! There are still other projects, that like this one but SP projects, love the AMD cards more. Unfortunately there is no 'one card fits all' for all the possible gpu projects.

Thanks Joe, it all makes sense now.

I've just read that for the GTX285 the DP performance is only 1/12 that of the SP performance, this would explain why it is faster than the GTX650 Ti even though it has a slower SP performance.

I think I'll buy an AMD card next time.

Best Regards,
Daniel

Other projects, like DistRTgen and PrimeGrid, LOVE the Nvidia cards MUCH more!! There are still other projects, that like this one but SP projects, love the AMD cards more. Unfortunately there is no 'one card fits all' for all the possible gpu projects.

Right, that's why I run both types. Most of the time my Nvidia card runs Einstein, GPUGrid, or PrimeGrid. I move it to MW mostly for challenges. The AMD cards are king on MW because of the DP requirement. They also do well on Einstein (SP) which has a very good OpenCL app for AMD.

Joe

Thanks Joe, it all makes sense now.

I've just read that for the GTX285 the DP performance is only 1/12 that of the SP performance, this would explain why it is faster than the GTX650 Ti even though it has a slower SP performance.

I think I'll buy an AMD card next time.

Best Regards,
Daniel

Other projects, like DistRTgen and PrimeGrid, LOVE the Nvidia cards MUCH more!! There are still other projects, that like this one but SP projects, love the AMD cards more. Unfortunately there is no 'one card fits all' for all the possible gpu projects.

Right, that's why I run both types. Most of the time my Nvidia card runs Einstein, GPUGrid, or PrimeGrid. I move it to MW mostly for challenges. The AMD cards are king on MW because of the DP requirement. They also do well on Einstein (SP) which has a very good OpenCL app for AMD.

Joe

Nvidia cards also do VERY well at DistrRTgen!!! If you are into points that is where ALL the top crunchers are.