PCIe 3.0 problems with fluctuating FPS

Well for starters, GPU works as it should on PCIe2.0 - always maximum performance when I need it, across all reboots/shutdowns.
On PCIe3.0 its pretty random, above screenshot was taken after a reboot, before the reboot it was working at maximum performance. So I don't know what else is to blame...
As I said in te OP, maybe the PCIe3.0 controller is faulty, but I dont know much about it...

 

May be dying 470 broke something in the motherboard. Have you tried another PCIe slot?

Also it is supposed to be of no importance for a single card - whether v3 or v2 mode (of PCIe) activated.

Sorry, I see the OS in OP... Have you tried Win8.1 ?


Have you checked for a videocard`s BIOS updates at the OEM`s site?

 

Gtx 470 died in my previous build, after I got the current one (3 months ago), I was using 8800gtx and for some time HD4600.
Yep I have alos tried second PCIe slot, same result.
I have updated to Win10, before I got 960, but I have tested in Ubuntu 15.04, and it has same issues.
Runing latest BIOS form Gigabyte for the motherboard and gpu.

I know that there isn't any considerable performance gains in PCIe2.0 vs PCIe3.0, but something is wrong with the more or less new PC, and its really bugging me :bang:

 

Check whether you accidentally turned on "spread spectrum" BIOS settings.

Obviously PCIe controller is in the CPU. But motherboard holds bus itself (and slots).

So you can check videocard in another rig. Clean videocard`s PCIe contacts with alcohol.

You can RMA CPU and then motherboard.

Edit: Have you installed Win10 in UEFI mode? If yes then have you disabled CSM module in BIOS?

 

Yeah I will try GPU and CPU in my friends PC, as soon as I can.
Spread spectrum is set to Auto, if I change it, it starts increasing, so I'm assuming its off by default.
I have installed Windows 10 in UEFI mode, but I have boot set to Linux. I have CMS options only if I set OS to Windows, so I'm guessing its disabled.
As for RMA, I will do it as soon as I know what component is faulty.

I have another idea, but it seems a bit far fetched. Is there a chance that the CPU has a bad connection with the motherboard, so that reseating the CPU might help?

 

How do you know that spread spectrum starts increasing? I always assumed that both spread spectrum settings should be set to "off" to permit more stable work and more higher overclock. If settings have values "off" try to set it.

Well, select Windows as boot OS and disable CSM - to be sure. And then select Linux back.

Well, it can be but I guess in case of bad connection PCIe would give you BSODs or malfunctioning devices in any mode. But you can try.

 

Have you tried the other PCIE slot? It's only 8X but that wont affect performance.

My second guess would be Windows 10 issue with mobo chipset or GPU drivers. Can you try it on Win 8.1?

 

Sadly there is no "off" settings, by default it's auto, changing it just increases the value. By that I'm guessing that it's hopefully off.

Just tested this, no success.

I have tried second PCIe slot, does not help. I have Ubuntu 15.04 installed and its having same issues as Windows 10, so I think its safe to assume that Windows 8.1 would have same issues.

 

Which revision of Gigabyte Z97X Gaming 3 do you own?

 

It should be Off unless you are having interference problems.

 

It's rev 1.0.

 

Problem is BIOS at this motherboard has spread spectrum setting as a combination of combobox and a slider. When combobox is in "Auto" the slider is in most left position assuming (???) 'off'.

I`d say such UI approach is confusing.

 

Tested the GPU on my friends setup and it's working all fine. Hopefully I'll test the CPU asap.