“How To” Mine With AMD And Nvidia Cards In The Same Machine

After stumbling onto Craigslist, and finding an incredibly cheap GTX 970, I knew I was in for an adventure. I picked up the card from the seller, brought it home and attempted to get it hashing. To no surprise, I struggled getting it to work along side my two other AMD cards. After hours of torture, here’s what I went through, and how I found a solution.

Installation

Installing the new GTX 970 into my rig was incredibly easy. All I had to do was push it into the riser, and run another power cable from my power supply.

Drivers

This is where we got into a pickle. I figured the only way I could get both cards hashing would be to install the drivers for both of them. Sounds simple, right?

After installing them, I gave the machine a quick reboot, opened up the device manager, and saw the 970 was non-functional due to “driver error”.

I decided on uninstalling my “15.12 Crimson drivers”, for the AMD Cards, and removing the cards from the machine. In which I left only the GTX 970 connected. After rebooting, I was happy to see the GTX 970, was fully functional with no errors. I then re-installed my AMD drivers, and decided to try the newest ones, instead of “15.12 Crimson”. I put back in one of AMD cards… And after yet another reboot, my 280x was not being discovered… At all.

I went through reboot, after reboot, and countless failures attempting to get the drivers to coincide, and recognize both cards. Until finally, after six hours of tinkering, I found a solution.

I removed all drivers and cards from the machine, aside from my HD 7970(AMD) card. I installed the “Crimson 15.12” driver, and rebooted my machine. It was being recognized, as predicted. From here, I turned the machine off, installed my 280x(AMD), and turned it back on. As predicted again… It worked. I removed the Radeon software, and only kept the driver that was needed to keep the cards functional(not sure if this actually did anything). Afterwards, I shut down the machine again, installed my GTX 970, turned it back on, and installed it’s latest drivers.

To my surprise, after another restart, it somehow worked. Buy, isn’t this the same combination/installation process I had went through originally?

Yes!

However, I had switched my primary card(GPU in the 1st slot) from an AMD card, to the GTX 970. So, the Nvidia card had been the one powering the display.

In a summed down version, here’s what I did to make it work… :

• Install the AMD cards and “Crimson 15.12” drivers as you would normally.
• Turn off the machine, and put your Nvidia card in.
• Ensure that it’s in the first PCIE lane, and it’s the one used to power your display.
• Install the Nvidia drivers, for your card.
• Reboot.

Also, be sure to run two different miners, and ensure that one of them has only the AMD cards enabled, and the other has only the Nvidia cards enabled.

The use of Claymore’s Nvidia+AMD miner didn’t seem to work out. As it’s one program, calling on both different cards/drivers.

Also, make sure you don’t… :

• Install the Nvidia drivers before the AMD drivers, it won’t work. I tried.
• Install both of the AMD cards at the same time, just to be safe.
• Break anything out of frustration. This was difficult for me.

The Aftermath

I thought that I had done it, and my long life goal was finally complete. Sike!

My fan speeds were locked on MSI afterburner, however I discovered that the AMD cards required a “Dummy plug“, to unlock them.

After twelve hours or so of the rig mining, it crashed. Leaving some funky looking lines on the display… Sounds like a gpu driver related issue no?

I worked for a few more hours attempting to get it to stop crashing like so, but I couldn’t wind up finding a solution.

In Conclusion

The rig is stable, aside from needing to restart it once a day or so… If you don’t have any choice, and really want to get your cards hashing, this guide is a lifesaver! However, in the long term, I’d recommend either selling off the odd card out, or putting it in separate machine.

I could be wrong, and this issue could be only with my specific model cards. However, I believe the best way of avoiding the issue, is by not setting up a scenario in which issues can happen.

Also, this guide only applies to people using the cards to mine cryptocurrency with. Machines made to render content, and etc shouldn’t have as many issues, and may end up being stable. It’s a different story if you aren’t pushing your hardware at 100%, 24/7.

Sadly, I can’t recommend the constant maintenance it seems my rig needs… To anyone.

I’ve decided on re-selling the GPU for more, and using it’s money to buy an AMD card… Probably another 7970.

Best of luck.