First post here, hope someone can help with this one
I have a gaming pc with these setup
Mather ASUS Rampage IV Extreme
Core i7-3930 3.2Ghz
16GB Ram Patriot DDR3 1333
EVGA GEForce GTX 660 (Latest drivers)
 
The PC was behaving ok, my kids played Star Wars Battlefront and Battlefront II (the new games, not the old one) and some other like Apex Legends, NFS Rivals, and so on...
All of a sudden, the games started crashing, sometimes even in the opening menus, like just everything freezes, the PC is unresponsive, and we need to hard reboot,
After several months trying everything (cleaning and changing cooling paste, completely disassembling the PC, cleaning every bit of dust, moving card to different PCI-E socket, measuring power supply voltages with a multimeter to make sure that's ok, updating every single driver, etc) in the middle of which we noticed an important overheating in the gpu card, I came across some forum where it was adviced to run Asus PC Diagnostics software.
I did, and then I found an error when the video card tests are being executed (the test displays a texture as background, and a "3d crystal ball" traveling accross the screen, and then the image freezes.. same thing as happens with the games)... the error in the Error.log file says:
 
"Error Occurs In PlayXTestMain Line:553,EC=0x80040905"
 
That's all I get. I googled it, nothing found.
 
On the other hand, also in the process, I noticed that when trying to overclock the mobo I get an error message during POST like "Overclocking Failed..."
 
Any ideas???
 
Thanks in advanced

Almost assuredly solder on the PCB has cracked somewhere..That was not uncommon with cards of that era and can cause a Pandora's Box of issues.

You can disassemble and bake the PCB (aka the 'oven trick') like this (lots of other videos too) to reflow any solder cracking that might exist..I certainly would..Then hope for the best.

If you bake it, it's important to do it with the GPU chip-side up and not down, otherwise larger/heavier surface-mounted components may fall off in the process.

Baking may only fix it for a short time, or a long time, or not at all..I have an old EVGA 9800 GTX that I baked like 5 times within 2 years, but hey, it still works perfectly fine..I bake at 200C/395F for 10 minutes.

Never seen it. If your system is having issues when overclocking you need to set your hardware back to default clocks.