Maximus V Formula - 1st PCIe 16x slot stuck at x4 link speed

[NLight95]

The first PCIe 16x slot in my Max V Formula is stuck at x4 link speed and despite re-flashing to several different earlier BIOSes (1309, 1408) and disabling C3 & C6 reporting, it doesn't change. I'm using a Sapphire 7970 OC. Moving it to the second 16x slot shows an x8 link speed, and the third at x4 (both of them are operating properly accordinfg to the manual). No other expansion cards are installed, just the 7970 alone.

I've owned my MVF since last July but only noticed this recently because I had no need to play around with the NB PCIe Configuration. It was after I saw the results in GPU-Z & CPU-Z, then confirming it in the BIOS itself (currently 1604) where the Link Speed is showing as x4.

Any help would be appreciated. Thanks!

This is what I've tried thus far:

1. Blow out PCIe X16 slot one with compressed air
2. Reseated 7970 (several times) and reinstalled 3570K
3. Reset to BIOS defaults
4. Flashed back to both 1408 and 1309 BIOSes but no change, so went back to 1604
5. Tried different Gen settings with no effect (it's not the problem anyway as PCIe 3.0 is working)
5. Tried my old HIS 4890--same results, link speed stuck at 4 (it's a Gen2 card with a 16x link)

CPU-Z


GPU-Z, 7970 at idle



GPU-Z, 7970 under load

[NLight95]

NemesisChild wrote:
Have you tried reverting to an older bios, like 0804?
This is the bios that I've been running ever since I bought the MVF.
No problems whatsoever with 0804, rock solid stable as well.

I haven't re-flashed back to 0804 it but will try and see if it changes anything. ROG Exchange only goes back to 1309 and I'd like to use that feature.

Update:

I flashed 0701 and the link speed is still at x4.

[MadIce]

I used to have the problem the OP describes with two 5850 cards in an other MB. I had to remove the cards several times and put them back in again, before the correct number of lanes kicked in (8 lanes in my situation). Not sure what caused it. Maybe I didn't align them properly or it was a scratched contact. Dust? Used compressed air to clean the slots. But in the end it worked.

[NLight95]

MadIce wrote:
I used to have the problem the OP describes with two 5850 cards in an other MB. I had to remove the cards several times and put them back in again, before the correct number of lanes kicked in (8 lanes in my situation). Not sure what caused it. Maybe I didn't align them properly or it was a scratched contact. Dust? Used compressed air to clean the slots. But in the end it worked.

I appreciate your effort to help but I tried what you did, several times, with no success. I have a portable air compressor (much stronger than compressed air in a can) and blew out the slot thoroughly at least three times. And as I originally posted, I tried my old 4890 with the exact same results--so that eliminates the 7970 as being the source of the problem.

Some have told me that the issue I'm having doesn't make a difference as far as overall performance goes but that doesn't take into consideration future video cards which may easily exceed the bandwidth of an PCIe 3.0 x4 link speed, not to mention that I paid for a motherboard that should operate as advertised. If it didn't matter to me then I would have purchased a SB processor rather than an IB 3570K. I may have to RMA the board because I've exhausted all possibilities to get it to work.

[Chino]

1. Reflash your BIOS to 0804 using the USB BIOS Flashback feature.
2. When the reflash is completed, power down your system.
3. Remove your GPU.
4. Remove the CMOS battery for 5 minutes then insert it back in.
5. Install your GPU and power up your system.
6. Upon power up, enter BIOS and load the optimized defaults and save.

Does the problem persist?

[NLight95]

Chino wrote:
1. Reflash your BIOS to 0804 using the USB BIOS Flashback feature.
2. When the reflash is completed, power down your system.
3. Remove your GPU.
4. Remove the CMOS battery for 5 minutes then insert it back in.
5. Install your GPU and power up your system.
6. Upon power up, enter BIOS and load the optimized defaults and save.

Does the problem persist?

I did exactly as you said above and Yes, the problem still persists.

[cenberci]

Hİ DİD YOU SOLVE THE PROBLEM?

BECOUSE İ HAVE EXACTLY SAME PROBLEM

Asus Maximus V Formula 1st PCI-E slot is stuck at 2x
But my second slot works fine at 8x
so my cards are now working 2x/8x SLI
my card is asus gtx 680 SLI
pls i need help
PLS HELP

[Chino]

The problem seems to be caused by a faulty PCIe lane. Looks like you have no other choice but to RMA the motherboard. Sorry, mate.