[Help] While gaming after a few seconds my monitor loses the signal

[aballara]

First of all sorry about my english, I'm from Argentina and I have a big problem with my R9 280x Sapphire Dual X.
I was cleaning my PC (I take off all the components and cleaned them up with latex gloves and all that stuff, also I opened my GPU and reaply thermal paste for second time) when I build my PC again all is going normal. I have windows 8.1, I can use it very well.

The problem is that when I run any heavy game (like BTF3, Dragon Age Inquisition, or even LoL) after a few minutes or even seconds my monitor lost the signal, and the fans of the GPU for a few seconds start to run at 100%, but only for 2 seconds, then all came back to normal (PC still running) except for the monitor (Samsung HD IPS 23') I've been using this rig since 2014 I its the first time that I having troubles.
Things that I read on this forum related to my problem:
-Can be a temperture ''scanner'' (I dont know how to call it) that te GPU have an its damaged
-Problems with the resolution scale and the monitor (The same problem and i tried with my TV)
-Drivers problem (I've tried to unistall all drivers of AMD and reinstall, also format my HDD and install Windows again, the problem keeps)
-Problems with the BIOS, need to update it
-The GPU is screwed
-High temperatures (This cannot be possible, my case have 5 fans runing (my CPU is watercooled) and I've never had problems before with temperatures

PLS help me I dont know what to do, the only thing I didnt tried before is to update or flash my bios. I sent an e-mail to amd for technical support a few days and they never answer me...

My rig:
Mother: Gigabyte z77-d3h
HDD 250gb samsung
HDD 1tb WD Blue
CPU: i7 3770 (watercooled with H100i)
GPU: Sapphire r9 280x Dual X 3gb
Ram: 8gb GSkill Trindent 2100mhz
Power Supply: Thermaltake Smart Series 650w
Case: Urban S1 White Edition Thermaltake
Windows 8.1

 

[aballara]

I've benn trying with BTF3. The first time the game looks to run well with the graphic options setting as ''auto'' (for me, almost all on ultra except a few filters) but the screen freeze (but not lost the video signal) and from windows says a message that the drivers from the graphic card stoped. Task Manager close the game and try again.
Second attempt: run the game windowed with the graphic options on ''auto'' and no trouble from about 10 minutes of gaming, then switch the grapich options to Ultra (Always played on ultra before) and after a minute or few seconds the game crashes and the video signal get lost, but again, the PC still running.

Now I'm sure that the problem is from the drivers or the Bios, and it isn the GPU