I have a slight problem with my Gigabyte GTX550TI OC card, about a month ago when i was playing it randomly crashed and shut down the whole computer, i waited a little then opened the case cleared the fans etc, thinking that it may have been a problem but it wasn't, since then it's randomly crashing, sometimes without any load, sometimes only when i'm playing a game for a few hours.
I have been using a gt430 since then, which was running without any problems at all. But i'm kinda annoyed by the fact that the gtx550ti is randomly crashing so I swapped the cards again and i'm looking around for solutions, i have tired underclocking the card to stock clocks which helped a little bit as first time i was able to run without any crash for 4-5 hours. I have disabled the nvidia hd audio as i read somewhere that those can cause some conflict with the audio drivers.
idle temp is about 54-55 C
load temp 70 C (but as I said sometimes it's crashing under load, sometimes it's running like a charm then crashes in windows for no reason)
i7 2600k @ stock
8 gb ddr3 1333 mhz
550 W psi (planned to be changed soon as it's about 3 years old now)
Linkworld lpm16-25, noname and bad probably. It's maybe the cause of that's why i'm planning to change it soon, but that's not explaining the fact that it was running without any problem for about half a year.
What PSU should I get?