Incorrect PCI-E Speed?

burninatortech4

Senior member
Jan 29, 2014
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368
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Setup:

AMD Athlon x4 760k (Overclocked 4.1-4.4ghz)
8gb 2133mhz AMD Radeon Memory
Gigabyte A88X-WIFI Mini ITX Motherboard
Gigabyte Radeon R7 260x 2gb

Concern: The R7 260x is rated as PCI-e 3.0 x16 capable but I understand that the 760k only allows PCI-e 2.0 x16 capability (would have to upgrade to 860k for 3.0 but I don't think that's worth it). My concern, however, is that the bus is only operating at x8, according to GPU-Z.

Question: What could be causing this? Is PCI-e 2.0 x8 going to bottleneck my 260x (compared to preferred 2.0 x16)? Any help would be appreciated.

Screenshots:

l13hdHd.jpg


f01UUNs.jpg
 
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burninatortech4

Senior member
Jan 29, 2014
661
368
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Depending on the GPU utilization is seems to switch dynamically between 'x8 1.1' and 'x8 2.0'. If that helps..
 
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BFG10K

Lifer
Aug 14, 2000
22,672
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PCIe down-clocks to save power when idle. Try running something with a GPU load and it should go back to normal.

If it still doesn't work, try updating your motherboard BIOS/chipset drivers, and see if there's any setting in the BIOS to control it.
 

Ampersand38

Member
Dec 8, 2012
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0
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Do you see the question mark next to the 1.1? Click it. That gets you a render test so your GPU will start working.
 

burninatortech4

Senior member
Jan 29, 2014
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The render test kicks it up to PCI-e 2.0 x8. It goes no higher.

My motherboards BIOS is F3. All that the F4 BIOS does is 'Update APU AGESA 1.1.0.2' according to the gigabyte website.

I don't see any settings in the gigabyte bios that have to do with PCI-e bus speed.
 
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SPBHM

Diamond Member
Sep 12, 2012
5,056
409
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try disabling pci express link state power management in windows power settings;

also, I think it's possible that if the card is not making contact properly with all the data paths it could work at lower speed, I know I remember seeing someone testing lower link speeds by covering part of the contacts with a tape...
 

ShintaiDK

Lifer
Apr 22, 2012
20,378
145
106
PCIe 3.0 vs 2.0 doesnt matter at all.

However it is strange you only get 8x.

Make sure you check the manual to see if there is some condition for the slot to be x16. But else I would check the contacts of the slot and the graphics card.
 

burninatortech4

Senior member
Jan 29, 2014
661
368
136
0EyTLqZ.jpg



I don't see anything in the manual about requirements for x16 or than a Kaveri based processor being needed for pci-e 3.0.

I also removed the card and reseated it. I also cleared the CMOS.

Nothing works. I'm totally stumped. Will x8 2.0 bottleneck a 260x?
 

ShintaiDK

Lifer
Apr 22, 2012
20,378
145
106
No it will not bottleneck you. However it is strange and not how its supposed to be.
 

ShintaiDK

Lifer
Apr 22, 2012
20,378
145
106
Even if you upgrade the graphics card to a highend, the impact of PCIe 2.0 x8 will be minimal to non existant.