Why is the D500 slower than the D300?

[Surfheart]

Been looking at the nMP trying to decide between the D300, D500 and D700, looking at lots of benchmarks, specifically openGL.

I wonder why is the D500 slower in these tasks than the D300? Hardware wise it would appear to be a significant improvement but the benchmarks all seem to show that the D500 is slower.

Driver issues or some underlying architectural differences?

 

[VirtualRain]

Been looking at the nMP trying to decide between the D300, D500 and D700, looking at lots of benchmarks, specifically openGL.

I wonder why is the D500 slower in these tasks than the D300? Hardware wise it would appear to be a significant improvement but the benchmarks all seem to show that the D500 is slower.

Driver issues or some underlying architectural differences?

The chips use different revs of AMDs architecture... The D500 and D700 are based on the Tahiti core which is optimized for compute (OpenCL) while the D300 is based on the Pitcairn core which is better at pushing pixels (OpenGL). Having said that, I haven't heard a compelling reason to buy the D500s yet. I bought them because the added cost over the D300s was minimal and at the time I ordered, little was known. If I was doing it over, I'd probably just opt for the D300s and put the savings towards a good bottle of Cognac because I'd likely get more satisfaction out of that than a bit of extra VRAM