Can't get dual Nvidia 960 cards to boot in a system

This should have been easy.

In my photo/video computer I have a GIGABYTE GA-Z97X-UD3H rev 1.1 motherboard with Windows 10. I've been running a Gigabyte Windforce 960 Nvidia 2GB video card, using it for Adobe Premiere Pro and Photoshop.

I replaced the 2GB card in the first PCI 16x slot with a nearly identical Gigabyte Windforce 960 Nvidia 4GB card, and that worked fine.

Then I tried to add the original Gigabyte Windforce 960 Nvidia 2GB video card as a second card in the PCI 8x slot...which should have installed close to transparently with just a bit of display juggling (I've had two cards running in systems before, but not this motherboard and these cards or Windows 10).

But I'm getting some weird faults. The system can't consistently find the OS on startup--it's not booting from C:

So I go into the motherboard set up and re-set the boot drive...which is mysteriously not the 0 drive as it should be.

No luck. OS is not found.

So I disconnect the power from my other drives, leaving only the 0 drive powered.

I go back into the motherboard set up...and again, it's moved away from the 0 drive. But with only the 0 drive powered, it finds the OS.

If I remove the second video card, everything is fine. Put the second video card back in--the motherboard cannot find the 0 drive to boot unless it's the only drive available.

BTW, the Adobe apps explicitly don't work with SLI, so I do not want the cards bridged.

To summarise:
All previous gear = Works fine
All previous gear + 2nd card = Faults
Most previous gear + 2nd card = Works?

Sounding like it could be an issue with either the power supply being under rated, or an issue with the power distribution in the motherboard itself.

What power supply are you running, and how many add in cards, drives, USB devices, and other powered items are you running?


Also, what specifically are you attempting to do with the second card?

Luckless wrote in post #18059710
To summarise:
All previous gear = Works fine
All previous gear + 2nd card = Faults
Most previous gear + 2nd card = Works?

Sounding like it could be an issue with either the power supply being under rated, or an issue with the power distribution in the motherboard itself.

What power supply are you running, and how many add in cards, drives, USB devices, and other powered items are you running?


Also, what specifically are you attempting to do with the second card?

All previous gear+2nd card alone=works fine

Power supply...maybe so. It's a 700 watt Thermaltake "gold" pulling the video cards, a USB port card, two SSD drives and two 3.5" drives (one a green drive at 5400 rpm, the other a WD black at 7200 rpm).

But those cards pull only 10 watts at idle--which would be the case at boot-up. They run up to 100 watts in gaming...which I don't do.

The only app I run that would even touch the second card would be Premiere Pro, and then only while rendering a final clip to output.

Are you using an SLI Bridge to link the cards?

Sorry, should have wrote that last one clearer. (Stopping in the middle of writing posts to respond to other things is a very bad habit.)

Using just the motherboard, CPU, Ram, Boot Drive, and both graphics cards is also failing, or will that boot into windows?

Independent graphics cards shouldn't impact drives and system booting.

Are you using any of your PCI-Ex1 slots? If not, then maybe try dropping the second card into the PCI-Ex4 slot all the way at the end. Skimming the specs for that board suggests that the x16 is on a shared bus with the x8 slot (So you have an x16 or two x8 slots, not a x16 and an x8.) and the x1 slots are all slaved over the x4 (So you can either use multiple cards in the x1 slots or one card in the x4)
It might at least get you limping along toward your goal and help narrow things down if that config works while an x16(8)/x8 is failing.

Also double check the power connectors going into the cards. Trouble shooting a workstation awhile back had three techie types in the office scratching our heads trying to figure out what was going on: Modular power supply in use, and the cables going to the graphics cards were never actually fully seated into the power supply.

-dave-m- wrote in post #18059774
Are you using an SLI Bridge to link the cards?

That's a no-no for Premiere Pro. It picks up individual cards--SLI will mess it up.

Luckless wrote in post #18059791
Sorry, should have wrote that last one clearer. (Stopping in the middle of writing posts to respond to other things is a very bad habit.)

Using just the motherboard, CPU, Ram, Boot Drive, and both graphics cards is also failing, or will that boot into windows?

With both cards mounted and only the boot drive (no other drives), yes it will boot into Windows. Then I shut down, reconnect the drives, and it fails to find the boot drive.

No, they shouldn't.

I'm using the first PCI-Ex1 slot for a USB extension board. I'm trying to put the 4gb drive in the x16 slot and the 2gb board in the x8 slot. I understand they will both run at x8 in that configuration.

Unfortunately, the x4 slot is blocked by my power supply from putting that double-wide 960 there. But I could try only one card in the x8 slot to see if that slot itself is failing.

Yes, I checked that.

Go to your bios & change the boot override.

virsago_mk2 wrote in post #18060044
Go to your bios & change the boot override.

I've done that multiple times. Somehow it "loses" the setting and winds up on one of the onboard USB ports. Moreover, the BIOS is supposed to default to drive 0 for booting...which is where I have the boot drive.

Right now I've got the new card in the PCI x16 slot getting some work done (the old card is laying on my desk). At first opportunity, I'll try moving it to the x8 slot to see if it's an issue with that slot.

Are these cards using the same driver? I dont think windows 10 supports two cards if they running to different versions of WDDM modes.

https://social.technet​.microsoft.com …?forum=win10itp​rohardware

http://discuss.topazla​bs.com …date-and-nvidia-gpus/8843

Windows driver conflicts would pop up after windows has booted. Or at the very least during boot, and wouldn't be able to impact whether the boot drive itself is found. It sounds like the OP is having issues well before he is even getting that far.

FerozeK wrote in post #18060472
Are these cards using the same driver? I dont think windows 10 supports two cards if they running to different versions of WDDM modes.

https://social.technet​.microsoft.com …?forum=win10itp​rohardware

http://discuss.topazla​bs.com …date-and-nvidia-gpus/8843

Yeah, same driver. I've used multiple video cards on older systems before--always Nvidia and always making sure they used the same driver.

If it only works when you unplug two of the drives or the second card that sounds like power to me.

What is the full part number off the power supply? Some of those Thermaltake PSs are absolutely awful.

Well, I'm operational now with both cards. Ultimately, the only thing I found wrong was that the SSD I use as a temp drive was non-responsive, or at least partially so. It may have been causing some inconsistent drive-shuffling during boot.

Added: All of which somehow deactivated my copy of Windows. I had to go through their chat to get it re-activated.

Seems like your main BIOS is starting to get corrupted somehow.

Similar symptom to mine 3 weeks ago where my boot order messed up & I had to manually change it everytime I boot up the PC. One day my PC won't boot up & doesn't show post screen, just blinking cursor on a black screen.

Found out that my BIOS was corrupted, luckily I can boot my backup BIOS & reflash the main BIOS with the latest version. Everything went back to normal now.