Bitcoin Forum

Hey everyone, I have a 6900 XT on the X16 slot and it works fine by itself. When I install 2 GTX 1070’s with a X1 to X16 Riser, windows lags and freezes a lot and I can barely move my mouse. All GPU’s get detected but when I start mining one of the GTX 1070’s disconnect amd the temperature of it is reported 0. I know both 1070’s work because they work perfectly bythemselves in the X16 slot. Why does the pc become unusable with the risers? I have a B550 Carbon and a RM750. Thanks.

Which windows do you use. I would recommend you Windows 10 Pro 2019 versions. Newer versions are not needed.
Install 2 GTX 1070s in X16 ports on the motherboard and connect the 6900 XT with a riser.
This is for testing purposes only.
The GTX 1070 is a great video card for mining, and works great with or without a raiser.

I use Windows 11. I can’t plug the 6900 xt on a riser because it is custom watercooled and the way the watercooling tubes go inside the GPU don’t allow it to be plugged in to another slot other than X16. So I have to keep the 6900 XT at the X16 slot. I am going to try HiveOS and see what happens. I know the 1070’s work in X16 because I tried them in the X16 slot of my friend’s pc

I am 80% sure that your problem will be solved when you install Windows 10.
Windows 11 is not the best operating system for mining on older video cards.
It will probably be faster to install the hive OS.
All 3 video cards consume no more than 500 watts and the motherboard no more than 100 watts, this does not seem to be a problem with a power supply.

I used molex to power the risers, can that be the issue?

Sure try it with a pcie 6pin in rise (no molex / no sata).
It may just be not enough power delivered. 

I don’t have enough 6 pin connectors to use on the riser, I am using all of the 6 and 8 pins for the GPU’s. Is the only solution to getting more pcie cables buying one more psu?

Remove a gpu or two to free up a plug to test and see if it resolves.