This does sound like a PSU problem.
i have a 20months old custom water cooled PC.
it worked smoothly the entire time untill last week when i was playing Battlefield Hardline which i have been playing for a while with no problems whatsoever. Last week the game froze and i got a crash error about directX hang, i looked over fourms and EA help and found out that its a common error, before trying any fixes i uninstalled and reinstalled my graphics card driver and installed directX(latest one was 12) my PC is running win10 x64bit i started the game again and instead of the freeze my monitors went black(i have 2 of them) and they gave me the "no signal" icon on the top corner like if they are not connected, the game sound kept going normally and i had a youtube page opened and the music didnt lag or stop.i tried everygame i could get my hands on(CS:GO, battlefield 4, battlefield 3, Dirt rally, project cars, just cause, gta v.. and so on) all of them gave me the black screen and i have no keyboard or mouse input at all since they both have LED lights and they turned off, i had to hold my power on key to force turnoff my pc, it doesnt freeze if not ingames, i tried a lower graphics game which is Heroes of Newearth and it took around 2 hours of gameplay to crash.(all the game i mentioned eariler were running on ultra settings, but i lowerd them to low and tried boarderless window mode. i suspected a gpu error so i ran prime 95 and furmark for about 35 minutes each and nothing happened. i underclocked my gpu and still the games crash. my temps are normal and they dont reach 70C even in the stress tests, then i ran ram Tests and tried the built in windows memory digiantostic and it gave me no error. i stress tested my CPU and no errors crashes or overheating, so i wiped out all my hard-disks and clean installed windows 10 x64bit again and downloaded few games again and they still crashed the same way with sound still normal, i wiped the hard-disks again and installed windows 8 same thing then 8.1 and the same thing happened and now i installed windows 7 and the same thing happened again. After reading alot of fourms and troublshooting i found out that it might be my PSU
which has a 650watt output and i checked using "fanspeed" and the UFEI bootmenu and found out that the +12v is at 12v and the 5v is at 5v and the 3.3v is at 3.34v so its pretty much normal i removed all my 4 RAMs and i know that the second ram slot from the cpu side is the "starting" slot so i installed and tried them one by one in that slot and windows launched normally which indicated none of them are faulty. i have no idea what i should do now and i do not want to buy a new PSU or GPU then find out that the problem was somewhere else.
Thanks you all for your time and effort.
My PC specs are:
ASRock Z87m motherboard
Asus GeForce GTX 760 DirectCu II
4 ddr3 4GB RAMs
Intel core i7 4700k
2 kingstone 120gb SSDs
cpu and gpu are watercooled and i have an extra 3 fans to keep everything cool.
I tried running Win7, 8, 8.1, 10 ALL x64bit
uninstalled and reinstalled every driver i could possibly install and tried all the 15 outdated drivers on nivida website.
Thank you again.