Hi guys,
 
my rig is as follows,
 
CPU : intel i7 5930K
RAM : corsair dominator platinum ([font="%value"]CMD16GX4M4A2666C16)(8 x 4GB = 32GB total)
GPU : gtx 980 sc acx 2.0 x2
PCI SSD : samsung 256GB M.2 NVMe PCIe 950 PRO SSD SM950 Solid State Drive
SSD 1 : samsung 250GB EVO 850
SSD 2 : samsung 500GB EVO 850
 
I bought a 3rd gpu today, converted it to liquid cooling and added it to my loop.
 
I was able to boot and log into windows all fine, I then went to 3dmark to run a test to ensure stability. During the first test (i disabled the video preview run) within 5 seconds or so my monitor started to flash random colours and then went black (at this point the system had frozen / locked).
I turned off my rig, and cleaned all my pci slots with compress air, and then swapped the card arrangement around (originally i had the new gpu as primary), with no luck.
I did noticed in my bios that when the new card was in pci slot 2 or 3, it was not picked up by my bios, however it did appear in device manager.
I tired using 3 different sli bridges as well the above with no success.
 
Any thoughts / idea's / suggestions would be much appreciated, as I'm hoping to avoid having to RMA a brand new card.

when i have all 3 running, they all register in device manager, without any errors or flags.
at present i have removed the new gpu and have reverted back to my original setup of 2 way sli, which is running fine.
 
i will try the new gpu in my old rig and see if the card is working on it's own over the weekend. I will post back the results by sunday afternoon.

psu evga supernova 1300 G2 less than a year old

Hey angelous86, I had the exact same problem with gtx 980 a few years ago when it was released.
 
2 way sli was working correctly with each of the 3 cards in all possible pcie slot. With 3 way sli I could only use windows interface, as soon as I tried to run a benchmark or a game the pc would crash no matter what. The only thing that solved the problem is when I finally decided to rma all 3 card because there was no way to identify  wich card was causing the issue.
 
If I can remember there was two other users with this problem who did the same.

sorry for the delay, been extremely busy with work.
 
should I just RMA the new gpu or should I RMA all 3 gpu's?
 
it seems to be only the new gpu which is causing SLI not to work, so I'm hoping to only RMA 1 card instead of all 3