jbfmello :
I built it myself, the psu is a corsair rm 650, cpu fx 8320 oc'd to 4.3 and the gpu is An r9 280x. Im sorry but i dunno what a ups is... This was Out of nowhere, and before the gpu stopped working it didnt shut down in safemode
UPS = Uninterruptible Power Supply - Essentially a battery backup with a built in line filter, low voltage protector (cause it goes directly to battery) and surge protector.
The RM650 should have no issues with the max load of your rig. Not knowing much about your particular PSU, I looked specifically at the negative reviews for it on Amazon. I also looked at many of the other 'frequent shutdown' threads on Tom's.
Though there are a lot of positive reviews, there is a significant number of negative reviews saying that the PSU crapped out, caused frequent shutdowns and/or had other issues that, in some cases, damaged their components, specifically the GPU.
If you have a spare PSU about even from another PC that can have some downtime, which most people don't but I gotta say it, swap the power supplies out and see what happens. It's now a case of trial and error at this point if you have the spares.
If that's not an option, contact Corsair, you may want to do that anyway. They may not like it, but their PSUs are under at least a 3yr warranty, and this one is 5yr. It should be a good unit, but, s[p]it happens.
(Other threads here also include MB issues, but unless it's a cracked MB, which is honestly pretty hard to do, there is usually a BSOD.)
Disclaimer: I am not a hardware technician, I've just built a bunch of machine through the years. (Had memory issues once, and one case of bad video drivers, once, with early Vista.)