890FXA-GD70 running PCIe at x8 and x2

John Carpio

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Mar 27, 2013
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ok heres my build...

MOBO: 890FXA-GD70 latest bios
CPU: AMD 1080T 6 core
VGA: MSI HD 6870
RAM: 8 GB Ripsaw
PSU: Corrsair 1050

ok so this all started with upgrades. i wanted to crossfire 6870's so i bought a second card. installed it in slot 5 booted it up. card showed it was running in at x2 in slot 5. i thought it was the card that i bought cause i bought it at frys and it was a returned item. so i returned the card and picked up a HD 7950. installed it. had a short in it so my comp didnt even boot. installed my original 6870 in slot 5 and showed x2 in CCC. contacted MSI for RMA, got my MOBO RMA's and got it back, installed it, with 6870. card shows x8 on CCC. with GPUZ it shows that the card when installed in slot 1 will only run at x8 when the MOBO says it will run at x16. So i RMA'd my 6870 since MSI support said the MOBO was tested before it left. Got new 6870, installed it. runs at x8. Put it in slot 5, runs at x2 according to both CCC and GPUZ.

i updated video card drivers, flashed my bios, updated CCC. i put it under stress tests to see if it was in power save mode or something. ive read a few things about flashing the GPU bios and updating the south or north bridge but i cant find drivers or anything for them.

i have no ideo what to do at this point. i have an RMA'd MOBO AND VIDEO CARD that just dont seem to work
 

John Carpio

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Mar 27, 2013
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10,510


according to the mobo specs slots 1 and 5 will run at x16 with no cards in slots 3 or 6
slot 4 runs at x4 only and doesnt share lanes with the others. with cards in slots 1,3,5,6 everything should still be running at x8
 

jessepage1989

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Jan 14, 2012
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I too am having the same exact problem. I have an MSI 890FX-GD70 and my video cards run at x8 speeds. I had a 5870 running at x8 for the longest time. There wasn't really an issue with this since it really didn't need all the bandwidth. But I just upgraded to a R9 280x (7970) and it too shows up as x8. However it shows up as PCIex8 1.1 until I play a game or render then it bumps up to PCIex8 2.0. Which there is a bandwidth difference between the two. So the only thing I can think of is that the MOBO throttles the bandwidth when the card isn't calling for it. I thought for sure though that getting a PCIe 3.0 videocard the thing would run at PCIe x16 2.0. Because PCIe x8 2.0 is like PCIe x4 3.0 or so I have read.