Gpu troubleshooting help

[InvaderIMD]

Ok so here is my thought; I have a Not working R9390 and a working 280X(which is in my pc at the moment)

Do you think putting the 390 in to slot 2 wile the 280 is in slot 1 then using Something like GpuZ ect to help find what might be wrong?

 

[AlternativeFactsForPresident]

What happens when you just put in the R9390?
I can't really help if you're not describing your issue.

 

[InvaderIMD]

Um it works if there is no Gpu drivers in 800X400 but then you install drivers and no vid out.

What happens when you just put in the R9390?
I can't really help if you're not describing your issue.