With the newest catalyst 10.7b driver GPU->CPU PCIe bandwidth's as low as ~800MB/s, which should be close to CPU->GPU bandwith that's ~4.9GB/s.
tested by PCIeSpeedTest_v0.2.
HD5870 with ASUS P6T7 WS X58, OS is Windows 7 x64, 12GB (6x2GB config) DDR3.
seems appeared only on Windows x64 systems...
i've just found there is a new benchmark program PCIeBandwidth.exe in %atistreamsdksamplesroot%\samples\opencl\bin\x86_64 dir.
interestingly, the result is:
Host to device : 2.61799 GB/s
Device to host : 1.97843 GB/s
could u guys run the benchmark and send the results for a comparison?