Build a rig that consists of 3x R9 390 and 1x 7950.
Started with the latter, added 1 R9 added 1 more and finally another.

Everything worked fine (Win7 64bit) eventhough i had to add a 2nd PSU (1400W) to aid my OCZ 700W psu.
These past 2 weeks things went downhill. System locked up totally, no response and had to power it off manually.
it would lock up after 2 days of mining, then some hours, very unpredictable.

I did sometimes see in the mining terminal that GPU1 had reported faults.
Tried to switch to a brandnew rise on that GPU, switch the PCI E port, even switched PCIE power cables. To no avail.
remove all AMD drivers and software, installed drivers ... No joy.

I finally left it out and the Rig has been stable for now, almost 24H and it looks like i am good now, but after this weekend i know that for sure.

Some specifics:

That problem GPU is exactly the same MSI R9 390 as one of the others, yet it runs 1000/1500mhz while the other one (problem free) runs 1040/1500.
How can they be different ?
Has the bios been altered (bought it used) ? underclocked ?

One of the fans has 1 broken blade (they are so fragile), could this have anything to do with it ? (temps are nearly the same as the other card, plus i put a 120mm fan to aid.


Any suggestions ?