(solved) PCI-E Bottleneck?

[potentafricanthunder]

I had an earlier thread that relates to this one. If I wasn't supposed to open a new topic, my bad :| - http://widescreengamingforum.com/forum/forums/multi-monitor-gaming/amd-eyefinity-discussions/19365/performance-issues-cfxd-685-s-and-


I decided to upgrade to two 6950's earlier this week and still get about the same FPS in almost all of my games (around 20-30 at high). I can understand a game like BF3 being too much for the cards..however my FPS doesnt seem to budge even I tone down the settings. Never break 30 fps.
According to the WSGF article on my cards, I should be getting a bit better than that. The only real difference I was able to track down is CPU and MB differences. But even then, I'm getting half of the performance in Just Cause 2 and Dirt 2 and that didn't seem right to me.
I was about ready to throw everything into a pit of fire when I came across the specs of my motherboard. Sort of a last ditch effort to see if there was something I was doing wrong. Turns out my board supports 2 cards...but only one in x16 mode. the other is 4x...
Could this be the reason for my crappy performance? I don't think i'm being bottlenecked by CPU or memory at this point.

If PCI-E is my bottleneck, would this be a suitable motherboard replacement? - http://www.newegg.com/Product/Product.aspx?Item=N82E16813188104



My setup btw is as follows
i5-760 (socket 1156) at stock 2.8ghz.
MSI h55-g43 MB -http://www.msi.com/product/mb/H55-G43.html#/?div=Basic
2x 6950 in Crossfire
16gb Super-talent DDR3 Ram
60gb Micro Center SSD
2x 1.5 WD Caviar Green HDD
3x 24' AOC e2343fh LED monitors.

I would rather not go up to 1155 if I can help it mostly because cheaper LGA 2011's seem to be around the corner....I just wanna be able to go zoom zoom on the road really fast!
Again, you guys have been a big help in anything that I've asked for help for. Hopefully when I get everything right, I can do some reviews!

PS - attached is my Heaven Benchmark for crossfire at 1080p and , not sure if it helps anyone at all.

Attached files

[Wijkert]

The answer to you question is no. The 4x slot would not be able to bottleneck your card: source. Something else must be wrong. No other hardware in your system should be bottlenecking your two gpu's as well. So it must be a software problem. Fresh win install, drivers etc. Can you tell me more about those?

[potentafricanthunder]

I have completely reinstalled windows onto the same ssd mentioned. I have played around with 11.12 , 12.1, and most recently the beta 12.2 release.

The only thing I haven't done is trying to install windows to a totaly different drive. I also hadn't checked BIOS for any pci-e options.

[Wijkert]

Do you have Afterburner installed, if not, do so. Run bf3 and see if both gpu's are used more then 80-90% of the time. And don't take this the wrong way, but you have both a crossfire cabled installed and activated crossfire in ccc right?

[sparx1981]

Completely agree that younshouldnt be experiencing a bottleneck. I sm running an i7 870 which is also a 1156 platform and i have run a 6990 and 6970 in trifire and also 2x 7970 in crossfire without issue. In fact im verey pleased with the setup. There are even articles out therenshowing that pcie speed and cpu speed have a minimal impact on performance. Most gains can be found with our gpu.

Your cards are pretty good so i would expect better fps. To give you an idea, my 6990 on its own could get abut 80fps on dirt 3, max settings and at a res of over 6000x 1100 ( i cant remember the exact res). Adding an extra 6970 boosted thisnby 10 or 15fps but that was due to it being trifire at that point. With 2x 7970s i get around 100fps at the same res and max settings.

If you need to chnge your mother board i recommend the P7P55de pro by asus. Its not too expensive but loaded with features. It has an auto overclock softwarem that gets my i7 870 to run at around 4.2ghz.

[sparx1981]

Sorry for the bad typing.... Apple hasnt invented an ipad with a slide out keyboard.

[potentafricanthunder]

Na, no offense taken.

I have the cable plugged into both cards and Crossfire is enabled.

I have NOT checked Afterburner, but will later tonight and let you guys know. Again, thanks for the help. I can usually figure out most hardware issues on my own but i am stumped.

[potentafricanthunder]

AB reporting that the cards are doing 80-90% across both cards...
But GPU2 is doing more work than GPU 1, I.e GPU1 can be doing 80 but 2 will be doing 86

[Wijkert]

AB reporting that the cards are doing 80-90% across both cards...
But GPU2 is doing more work than GPU 1, I.e GPU1 can be doing 80 but 2 will be doing 86

That seems normal anough. Can you tell me the 3dmark11 scores for both 1 and 2 gpu's?

[sparx1981]

it just struck me, what PSU do you have? perhaps your graphics cards aren't getting enough juice?
Also can you confirm that you have got the crossfire bridge installed?

[potentafricanthunder]

[quote]AB reporting that the cards are doing 80-90% across both cards...
But GPU2 is doing more work than GPU 1, I.e GPU1 can be doing 80 but 2 will be doing 86

That seems normal anough. Can you tell me the 3dmark11 scores for both 1 and 2 gpu's?

funny enough, I cant run 3D-Mark
closes right out when i started to run...

I'm considering wiping my machine a 2nd time to be sure everything's clean. just odd.


@sparx, CF bridge is installed.

[potentafricanthunder]

[quote]AB reporting that the cards are doing 80-90% across both cards...
But GPU2 is doing more work than GPU 1, I.e GPU1 can be doing 80 but 2 will be doing 86

That seems normal anough. Can you tell me the 3dmark11 scores for both 1 and 2 gpu's?

funny enough, I cant run 3D-Mark
closes right out when i started to run...

Another bit of odd news
looking at GPU-Z
Card one showing running PCI-E 2.0 16x
Card two shows running PCI-E 1.1 4x.

I'm considering wiping my machine a 2nd time to be sure everything's clean. just oddities abound here.

it just struck me, what PSU do you have? perhaps your graphics cards aren't getting enough juice?
Also can you confirm that you have got the crossfire bridge installed?

I'm using a Kingwin 1000w PSU

http://www.hardocp.com/article/2012/01/04/kingwin_lzp1000_1000w_power_supply_review/9

[Haldi]

GPU-z 0.5.8 shows PCI-E 3.0x16 @ x16 1.1

Thats because the mainboards Power Save features kick in and slow down PCI While Idle! Watch while running furmark or any other 3d Application.

[potentafricanthunder]

GPU-z 0.5.8 shows PCI-E 3.0x16 @ x16 1.1

Thats because the mainboards Power Save features kick in and slow down PCI While Idle! Watch while running furmark or any other 3d Application.

even running from Furmark and Kombustor...it shows as PCI-e 1.1

[Haldi]

In my BIOS i can manually Limit PCI-E Generation to wha i want! You. Sure everything is right in Bios? Maybe save Profile and do a Factory Reset after?

What do internet reviews say about your Mainboard? No Problems?

[potentafricanthunder]

None that I can find.....that problem isnt even mentioned on the website. Just says for 4 but makes it seem like it'll run at 2.0 speeds not 1.1.

I have everything taken care of tho.
Went out and got a i5-2400 and a MSI motherboard that does both cards at x8.
Now everything works like a greased charm.
I also now have pretty much a spare computer trying to troubleshoot the whole thing.
Thanks.