GTX 780 in 16x slot only running at 4x

[piccoevo]

I just purchased an EVGA GTX 780 SC. I got everything installed, and I used CPU-Z to make sure that the bus speed was running at 16x. I had the card installed in the very top slot, which was the 16x slot. I looked and the card was running at 4x. I installed it in the next slot down, which was the 8x slot. That one ran at 8x. Here are my system specs.

Motherboard: P8Z77-V LK
CPU: i7 3770k OC to 4.7GHz
EVGA GTX 780 SC
OCZ 700W PS
Samsung 840 Pro
Custom Liquid Cooling Loop
16GB GSkill 1866

I used my old card, a GTX 650Ti boost which had the same results
16x slot -> 4x
8x slot -> 8x

What could be causing this. The graphics card and motherboard are all a few days old. Please offer me any suggestions. Thank you.

Sincerely,

Blaine

 

[scout_03]

did you check in the bios is the gtx 780 is detect as first gpu ,settings this way pci-e/igpu .

 

[piccoevo]

did you check in the bios is the gtx 780 is detect as first gpu ,settings this way pci-e/igpu .

Yes, I tried every combination, yet the 16x port still runs at 4x and the 8x port runs at 8x.I don't see what it could be. The motherboard and graphics card are both brand new.

 

[qbsinfo]

i'll take a few guesses:

make sure the slot is clean so nothing inhibits it from reading a x16 card is in it.

boot into the bios > advanced > system agent > NB pci-e configuration (or something like that) > PCI x16 slot 1.
there are a few settings , auto, gen 1 gen 2. even though that has to do with pci-e 2.0 or 3.0 see if adjusting that may "kick it" in x16 mode.

also see if you need to update the BIOS since the board is new. i suspect it ought to be done anyhow.

if none of that works . .i think you may need to consider starting an RMA process or talk to who you bought the board from.

 

[scout_03]

all the driver for the motherboard are up to date even the one for the cpu graphic chipset and the motherboard .

 

[piccoevo]

i'll take a few guesses:

make sure the slot is clean so nothing inhibits it from reading a x16 card is in it.

boot into the bios > advanced > system agent > NB pci-e configuration (or something like that) > PCI x16 slot 1.
there are a few settings , auto, gen 1 gen 2. even though that has to do with pci-e 2.0 or 3.0 see if adjusting that may "kick it" in x16 mode.

also see if you need to update the BIOS since the board is new. i suspect it ought to be done anyhow.

if none of that works . .i think you may need to consider starting an RMA process or talk to who you bought the board from.

I tried switching the generation in the BIOS, which did nothing. is there anything else that could keep the bust from going full speed? I looked in the BIOS and didn't see how it could.

 

[piccoevo]

Thanks guys for the help! I reinstalled my CPU as a last resort and it finally runs at 16x! I was about to do a RMA, but everything looks to be good not. Thank you!