can we get someone with nvidia gfx to try this?
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can we get someone with nvidia gfx to try this?
@nsegative : Your GPU-Z says your'e using a PCIe x16 2.0 link, but those speeds are no where close! Is that truly a chipset bottleneck? Check your BIOS or something....wow....just wow.
Oh I see why. His CPU to GPU is ~4GB/s, but he has QPI. You have FSB so yours is not as high. Yes, that is normal for your setup it would seem...
Hold up, I take that back. The Core 2 guys over here: Intel Forum PCIe Speed Test don't have that issue. Something looks quirky about your results.
That is kinda weird. Both Intel systems with an X2 get the GPU -> CPU speed WAY lower than AMD systems with X2s, yet higher than AMD single card setups. jcool had normal CPU -> GPU bandwidth, but nsegative has half the bandwidth of AMD users. The difference between jcool and nsegative is jcool has an i7 with QPI, and nsegative has older fsb tech. the fsb cant really be limiting his bandwidth that much could it? And either way, why do both Intel based computers with 4870X2s have such low GPU -> CPU bandwidth compared to AMD?
EDIT: ya if you look at the guys with fsb based systems in the Intel section, they have more bandwidth than the AMD guys here with their HTT. So FSB definitely isnt a limiting factor. And since HTT has more bandwidth than FSB, something else is limiting the AMD system bandwidth.
Ran the test again here are the resutls. Also I don't have any problems running the test in Crossfire. Can run it over and over in Crossfire without crashes but disable Crossfire and it will crash every once in a while.
http://img5.imageshack.us/img5/5568/testfour.png
By knuckles6 at 2009-06-03
Oh that's my new toy on the desktop
Mechromancer said it takes 10-15 minutes somewhere in one of his first posts...?
Anyway, it's either that program being messed up, or really a driver issue, since we tested so many combinations it's gotta be one of those.
Gonna re-run with raised QPI and PCIe, hold on.
NM, it only takes about 5 minutes to run, if you system works right. I had some probs I had to fix when my system was running it in 10+ minutes.
Run #2...
4870X2, Server 08 x64 SP2, Cat. 9,4 - high QPI (7,68GT/s) and 110Mhz PCIe
http://database.he-computer.de/Bilde...PCIebandw2.jpg
Helped a little, but GPU--> CPU is still way too slow..
Oh and by the way, the app doesn't run with an NV card.. just tried on another i7 rig with a GTX260, just says ati something .dll missing...
I'm in the same boat as you jcool. Seems intel quads are affected by this.
With an X2, there is no option to enable/disable crossfire.. it's hardwired really, and can't be disabled.
Wow, Jcool's falls on its nose for GPU -> CPU for Peak Bandwidth.
I pushed my overclock up to 4.01Ghz and ran the test again and it made no difference in my results.
Going back to the weird options in the bios, I enabled the option to split the ht link and I got an extra 75ish mhz with the same vcore but I had to increase the nb volts slightly because its now running above 3.1ghz. But no extra performance for gpu to cpu with that for me.
I just ran the tool on my "old" MSI K9A2-Neo with AMD770 chipset and single PCIe slot - Sapphire HD4870 and GPUz says PCIe 2.0 @ x16 - Cat 9.3
All runs crash with GPU Recover when starting the last level of the test but up to there it shows : CPU->GPU 4.1GHZ & GPU->CPU 880Mhz .... I am guessing that is not good?
>>> delete <<<
IT IS NORMAL. Please read my orginal post and check out the link to the AMD Developer Forums. It usually crashes, especially on Vista because stresses the hell out of the system. Run it from the CMD prompt to make things easier too. Take all screen shots before it completely crashes out, maybe around the 256 to 512mb range. I say this because all of us see our max bandwidths well before that point in the test.