Will putting graphics card in the lowest PCI-E slots affect performance?

[elitherabbit]

Hi. I couldn't find much info pertaining to my particular case, so I'll cut right to it.

Here are the specs, right off the bat:
Intel Core i5-2500K 3.3GHz
Gigabyte GeForce GTX 670
MSI Z77MA-G45 mATX
Corsair Vengeance 8GB
Windows 7 64 Bit
Bitfenix Prodigy M
Cooler Master 700W

Long story short, in the Bitfenix Prodigy M you have to mount your motherboard upside down, like this (this is what it looks like right now):

Since I'm getting a new speaker system, I'm also getting a sound card (thinking of this one):
http://www.amazon.com/ASUS-XONAR-Headphone-Audio-Card/dp/B0045JHJSS/ref=sr_1_2?ie=UTF8&qid=1385600952&sr=8-2&keywords=asus+dgx

The sound card would be long enough to the point where it would block almost two of the three fans on my Gigabyte 670 where the blank spot is.

So I had an idea:

If I put the GPU up top, directly taking in air from my top two intake fans, and have the wifi and sound card below it underneath the PCB.

My only question is will this affect performance? I don't know if the second PCI-E slot is only 8x or what, so I just need a second opinion. Thanks for reading!

 

[Cons29]

based on specs, the 2nd pci-e is x8, i think it should be ok. Wait, sandy bridge is not pci-e ready correct? so you'll be getting x8 in pci-e 2.0?
now i am not sure
well, on the top of my head, do some bench marks now, while it is on the first slot. Note the results, try the other slot and test again. synthetic benchmarks would help as the numbers should be there (not just fps)

see if it will have some performance hit, before you buy the sound card. just an idea though, not too sure also

 

[elitherabbit]

based on specs, the 2nd pci-e is x8, i think it should be ok. Wait, sandy bridge is not pci-e ready correct? so you'll be getting x8 in pci-e 2.0?
now i am not sure
well, on the top of my head, do some bench marks now, while it is on the first slot. Note the results, try the other slot and test again. synthetic benchmarks would help as the numbers should be there (not just fps)

see if it will have some performance hit, before you buy the sound card. just an idea though, not too sure also

As far as I know sandy bridge just isn't PCI-E 3.0 ready. GPU-Z says I'm currently in PCI-E 2.0 x16 @ x16 1.1 . I'll try the benchmarks and post back.

 

[rounakr94]

Top slot runs at x16 and bottom at x8 AFAIK.

 

[elitherabbit]

based on specs, the 2nd pci-e is x8, i think it should be ok. Wait, sandy bridge is not pci-e ready correct? so you'll be getting x8 in pci-e 2.0?
now i am not sure
well, on the top of my head, do some bench marks now, while it is on the first slot. Note the results, try the other slot and test again. synthetic benchmarks would help as the numbers should be there (not just fps)

see if it will have some performance hit, before you buy the sound card. just an idea though, not too sure also

Alright, here's my score before changing it to the top slot: http://www.3dmark.com/3dm11/7571329

And after: http://www.3dmark.com/3dm11/7571445

Pretty much no difference. But for some reason now my power supply is making a weird faint buzzing noise... hmmm

 

[cookybiscuit]

Coil whine, pretty common. You can try to fix it by unplugging the system and holding the power button down for 10 seconds, also there are certain BIOS settings (on board audio, boot from PS/2 keyboard etc) that you can use to mess with how much power the system uses to try and get rid of the noise.

 

[elitherabbit]

Coil whine, pretty common. You can try to fix it by unplugging the system and holding the power button down for 10 seconds, also there are certain BIOS settings (on board audio, boot from PS/2 keyboard etc) that you can use to mess with how much power the system uses to try and get rid of the noise.

Haha right as I posted that it went away, but if it comes back I'll be sure to try that.

Edit: Looks like it all worked out! Cons29's suggestion helped, and I saw little to no performance hit from running it in the bottom slot (which does run at 8x). Looks like I'll have the card in a few days! Thanks guys!

 

[Cons29]

enjoy it bro. i also have a 670 and an asus dx (i think its a dx, cant remember) xonar sound card, but on a bigger mobo