GTX 970 only works in x4

[Jacob_sluis]

I own a PC with 2 GTX 970 running in SLI. I got a performance issues with stuttering. One of my GTX 970 is running in PCIE x4 and not x8. The other GTX 970 runs x16 if i put it into PCIE 1 and x8 if i put it in PCIE 2.

The defect one is running on ALL PCIE slots at x4. So its nog about the mobo. Updating drivers the mbo and GPU did nog work and i dare not to flash the bios.

But since the other gtx 970 will run at x16 and the other doesnt, it looks like a malfunctioning GPU...out of the warranty. Any suggestions?

full specs:

Gigabyte GA-z170SLI XP
i5 6600k
MSI GTX 970 2x sli
Corsair dominator platinum 4x4 gb DDR4 2666 mhz
Cooler master Silent pro gold 800w
Antec GA 300 window
Cooler Master Hyper evo 212

thanks!

 

[clutchc]

According to the board's specs, the 2 x GTX 970 should each be operating at x8 lanes if you have them in PCIEX16 and PCIEX8 slots... and have no other cards in any of the PCIE slots.
http://www.gigabyte.com/products/product-page.aspx?pid=5496#sp
Is that what you have?

 

[Jacob_sluis]

Hello Clutchc, thanks for your support. I understand that in SLi both lanes should be x8 x8x gen 3.0, but it performs on x8 x4 in sli. I have a soundblaster and an M2 sata SSD installed, but they are not the problem. Removing the Soundblaster did not work. Removing the SSD is something i didnt test since my OS is installed there.

But it should not be the problkem, since i have two identical GTX 970 GPU's, and one is performing fine at x16 with a single card configuration setup on the top most PCIE. When I usew GPU #2 in a single GPU setup in the top most PCIE, it will only perform on x4. So it must be the card?

I have three hypothesis:

#1: the GPU is damaged. All the connector pins look fine but it could be anything in the card

#2: maybe GPU#2 had been working on x4 since i installefd the soundblaster and somehow remembers being in that state?

#3: same as option 2, but then with the motherboard?

I have reinstalled all the drivers except a BIOs flash. Is that reccomended?

 

[maxalge]

Hello Clutchc, thanks for your support. I understand that in SLi both lanes should be x8 x8x gen 3.0, but it performs on x8 x4 in sli. I have a soundblaster and an M2 sata SSD installed, but they are not the problem. Removing the Soundblaster did not work. Removing the SSD is something i didnt test since my OS is installed there.

But it should not be the problkem, since i have two identical GTX 970 GPU's, and one is performing fine at x16 with a single card configuration setup on the top most PCIE. When I usew GPU #2 in a single GPU setup in the top most PCIE, it will only perform on x4. So it must be the card?

I have three hypothesis:

#1: the GPU is damaged. All the connector pins look fine but it could be anything in the card

#2: maybe GPU#2 had been working on x4 since i installefd the soundblaster and somehow remembers being in that state?

#3: same as option 2, but then with the motherboard?

I have reinstalled all the drivers except a BIOs flash. Is that reccomended?

that motherboard has three x16 pcie slots



the top two run at x8, x8 when in SLI


the third only runs at x4

 

[Dragos Manea]

Hello Clutchc, thanks for your support. I understand that in SLi both lanes should be x8 x8x gen 3.0, but it performs on x8 x4 in sli. I have a soundblaster and an M2 sata SSD installed, but they are not the problem. Removing the Soundblaster did not work. Removing the SSD is something i didnt test since my OS is installed there.

But it should not be the problkem, since i have two identical GTX 970 GPU's, and one is performing fine at x16 with a single card configuration setup on the top most PCIE. When I usew GPU #2 in a single GPU setup in the top most PCIE, it will only perform on x4. So it must be the card?

I have three hypothesis:

#1: the GPU is damaged. All the connector pins look fine but it could be anything in the card

#2: maybe GPU#2 had been working on x4 since i installefd the soundblaster and somehow remembers being in that state?

#3: same as option 2, but then with the motherboard?

I have reinstalled all the drivers except a BIOs flash. Is that reccomended?

that motherboard has three x16 pcie slots



the top two run at x8, x8 when in SLI


the third only runs at x4

This is not the issue, if you look carefully op stated that the defective card worrks at x4 on all slots no matter the slot.

OP try to clean the gold pins with alchohol maybe they are oxidated.

 

[Jacob_sluis]

Thank you Dagos Manea, that is exacly right. But i have another thing:

In benchmarks, i dont see a lot of performance drops (Valley score 2400 on 1440p and high settings for an average of 60 fps) on the bad card, running at x4 gen 3.0. Nivida states that an GTX 970 cannot run at x4 at al.

So when i look into GPU-Z: thats where i see that the card (stressed) works a x4 3.0. But In the Nividia Control panel it s says:

Bus: PCIE x16 gen 3.0

I dont know if the nividia control panel only detects the specific slot (which is a x16 gen 3) of the speed that the card runs. If it is the latter, than GPU Z reads my PCIE wrong?

 

[Dragos Manea]

Yes , you are correct the nvidia control panel detects only the slot not the speed. Try to update the bios of the videocard maybe it is just a sensor error how you said. Well if anything performance related is ok i think you should not bother with details.

EDIT: for me for exemple had a ASrock z68m-usb3 and updated to a beta bios since then the videocard according to gpu-z is running at x8 speed but when i flahed the latest stable bios the card showed as x16 again, so it could an error from the motherboard too.

 

[Jacob_sluis]

Thanks again for yopur reply. I am not aware that you can updatee the bios of the videocar. Got any leads?

 

[Dragos Manea]

Never had a MSI videocard, only asus it seems that msi dont have bios updates. Asus has and presumed that MSI has too.

 

[Jacob_sluis]

Hello Dragos Manea,

I just went to the local drug store and bought medical alcohol and cleaned the connectors, with no result. i guess the card is bust so ill go and replace it. Thank you so much for helping me out.

 

[madmatt30]

Pcie 3 x 4 is still as fast as pcie 2 x8.

Even running x4 you're not going to see that much of a performance drop off in sli performance mate

Certainly not enough to warrant replacing the card at your own cost.

I've also never seen an instance when a GPU is at fault running at a lower bus speed - it'll be entirely down to the board IMO.

 

[Jacob_sluis]

Hello Madmatt30,

Interesting point and you may be on to something. Here's what i just found out:

Benchmarking both cards individually on Unigine Valley results in almost exacly the same scores:

test 1:
GPU 1 (x16) = score: 2478, average FPS 59,2, max FPS 113

test 2:
GPU 2 (x4) = score 2472, average FPS 59,5, max 115

test 3:
GPU 1 (good one) on top PCIE slot running at x8 and GPU 2 in second PCIE slot running at x4 and SLI disabled (so basicly using only the top card at x8)= score 2476, average FPS 59,2, max FPS 115.

test 4:
same as test 3 but witrh SLI enabled= score 4354 (!), average FPS: 101, max FPS 165

So, I see that it may be the case that both GPUS work on different speeds, but for a performance point of view:

- x16 yields almost exacly the same FPS as x4 (115 vs 113 fps)
- SLI almost doubles my benchmark score from 2400 to 4300.

Basicly, both my GTX 970 cards work exacly the same in the benchmark. But still, in games like Overwatch, Batman and Deus Ex i got a performance issue where one GPU works better than 2 in SLi... weird. Any suggestions?

 

[madmatt30]

Overwatch - broken sli support
Deus ex - broken sli support
Batman arkham knight - no sli support (you can force it in nvidia settings but you may gain ,4-5fps at the expense of bad latency)

What you're seeing is simply the limitations of a dual card setup when a title doesn't utilise it or utilises it badly.

Google nvidia inspector & you'll see ways to force better scaling at least on overwatch & deus ex - there are downloadable profiles available a lot of places.

I've not seen a new title properly optimised for sli/crossfire this year in all honesty.
A lot of older titles you'll get damn near 100% scaling , new titles you'll get nowhere near that & half the time extra problems.

 

[Jacob_sluis]

It is fixed! What exactly was the cause is uncertain. Both cards perform identical eventhough one card runs at x8 and the other at x4 in sli.

I did;
- Qflash the bios to f6 which let me enable xmp so my ram could run at native 2666 MHz (not sure related to the issue)
- install Nividia inspector and ran the overwatch sli profile
- run overwatch in full screen instead of borderless window

Tada: overwatch jumped from 40fps to > 200

Deus ex md is a different story but I found out that it performs dreadful on sli.

Thanks!