I5-750 bottleneck or pcie bandwith?

[vertical777]

hi I have an intel i5-750 running on stock clocks on a ASUS P7P55D mobo which has 2 ATI 5770s in crossfire,
when I run Crysis on max settings, I get stuttering on heavy action. Is this because my mobo has x16/x4 or is it because my cpu being on stock clocks bottlenecks my 2 gpus?
other games like CoD:WaW runs fine on max settings. Splinter Cell Conviction slightly stutters on max settings.

can someone help me on this? I'm planning on buying a coolermaster v8 so I can overclock my cpu safely.
Thanks in advance.

system:
intel i5-750
4Gb DDR3 ram
asus p7p55d mobo
1TB WDC green HDD
coolermaster HAF X case
ATI hd 5770 crossfire

edit:typo

 

[Maziar]

Hello
Your CPU is fine,that problem is because of your motherboard which supports CF at x16/x4.This speed doesn't perform very well compared to dual x8/x16,that's why it doesn't perform very well in demanding games like Crysis.

 

[vertical777]

thanks, do you think this here would be a good replacement(I would not say upgrade in this case) for my current mobo?

 

[Raidur]

Make sure you have your Crysis updated, so crossfire is possible.

4x shouldn't be TOO bad for a 5770.

What settings are you playing on Crysis? It takes a LOT of GPU power to max out AA in DX10 Crysis.

 

[vertical777]

don't you think 2 5770s can do all settings maxed out + full AA? that's what I have set now.
another thing, is it worth it to replace my current board with something that has dual x8? the difference between x16/x4 and x8/x8 not very clear to me since there's very little info on it on the net. almost all compare x8/x8 with x16/x16

 

[aznshinobi]

A great budget mobo is the MSI P55A-G55.

http://www.newegg.com/Product/Product.aspx?Item=N82E16813130292

It'll allow you to run 8x/8x or single 16x. Also if you worry about 8x/8x vs 16x/16x there is no real world difference. The difference between the two is only 1% of real world performance, and its hardly noticeable.

Scaling of 8x/8x vs 16x/16x: http://www.techpowerup.com/reviews/AMD/HD_5870_PCI-Express_Scaling/25.html

Hope that helped. The V8 is a great cooler, either that or the Cooler Master Hyper 212+ is a great cooler, since for the Hyper 212+ you can actually have dual fans on the heatsink, plus its a phenomenal heatsink for the same price as the V8. Though personally i have a v8 i love it.

 

[Raidur]

don't you think 2 5770s can do all settings maxed out + full AA? that's what I have set now.
another thing, is it worth it to replace my current board with something that has dual x8? the difference between x16/x4 and x8/x8 not very clear to me since there's very little info on it on the net. almost all compare x8/x8 with x16/x16

GTX 480 loses only 7% on 4x.

Crysis is a pretty demanding game. Maybe we can test your cards with 3dmark score comparisons?

 

[vertical777]

I only get roughly 17.5k 3d mark06 marks in total >>CPU+GPU tests on default
the cpu gets a small 4K of that 17.5K

that scale shows that there's a 7% loss when using the GTX 480 on a x4 2.0 slot
will those numbers hold for SLI/Crossfire builds?

EDIT: If ever I decide to change mobos I think I'll go for that MSI P55A-G55 or the P55-GD65 which is a little less greater than the former.

 

[Maziar]

thanks, do you think this here would be a good replacement(I would not say upgrade in this case) for my current mobo?

Yes that would be good,dual x8 will give you a good boost in performance

 

[kg4icg]

If you have your settings set too high in Crysis, you will get stuttering. CF 5770's are about the same as sli 260 GTX's. Best bet is to set the video in medium to handle Crysis. It's not like you have 5870's.

 

[vertical777]

Best answer selected by vertical777.