System shut off issue

Hey guys. I just recently got a new machine built (3 weeks ago), and up until today all has been well. Today i bought a new video card (which has a lower power draw then my old card) and installed it. Then suddenly, after a few hours, it just shut down and the power button wouldn't respond until I unplugged the power and plugged it back in. Now as I said.....up until the installation of the new card it was great. here are my system specs.

AMD FX-8350
Asus M599X Rev 2.0 Mobo
16 gb of Kingston HyperX ram @1600
Seagate 1tb HDD
New GPU Gigabyte 650gtx Ti oc 2gb. (With 1 6 pin power Connector)
Old card was the Zotac 9800GTX+ 1gb (With 1 8 pin power connector)
Thermaltake Tough power W0104RU bronze PSU @ 650W
Windows 8 Pro

I realized I never uninstalled my old card or the drivers to do a clean install. So when i plugged in my card (and the extra power pin) It just loaded up from what was already on my system. I then got some beta drivers that work with Crysis 3 open beta. Now I realize that it could have been a bad driver conflict. However, i am used to seeing the BSOD or a lock up when a driver conflict occurs. would this be the cause? I did uninstall all of my nvidia stuff and my GFX card and did a squeeky clean install of it. I even looked over my mobo to make sure no caps are going, and it came up clean. I am hoping it solved the issue...but does anyone have any other suggestions on this issue?

Have you made sure the inside of the case is clean? Overheating can cause that. And when I lived in the Seattle area, I had to clean my rigs every 3 weeks or they overheated. Yes the air was that dirty in the Kent valley.

my case is super clean as it is new. I read somewhere that a PSU will lose about 10% power capacity per year (depending on the usage) and I never turned my system off, aside from rebooting. If that were true...my 5+ years old PSU would be drawing an average of 417 watts.....which would explain why my system shuts off after i installed the new vid card and put it under any good amount of load. I just bout a 725watt PSU and installed it. Hopefully it will return to stability.

What are your thoughts on the the PSU power loss theory if you have any. I am curious to know more about this and see how true it is.

I agree with the caps failing and power supplies deteriating as time goes by. Seen it happen a few times. I used a AC amp meter to verify the draw.
So replaced the PS, 480 with a Xion 600 and that was a overkill per this site.
http://www.extreme.outervision.com/p...ulatorlite.jsp

7 years and it still pulling like it should.

Yea. I used that calculator. My pc would need a 450 watt psu. Add 30% and i get 600. So my 650 watt from 5+ years ago at 10% power loss per year would put it at about 417watts. My new vid card took it over the top and it couldn't handle the slightest load.

Things working OK now?

So far all seems well. Hope it was the issue. Good chatting with y'all again. Best tech support ever :)

I never heard the 10% theory... And I'm using an 8 or so year old Dell that started with a small psu... On the other hand - nothing lasts for ever and a failing supply can cause what was happening.

DrMDJ is the one who brought it to my attention initially.
But you are right a light pull on the power supply does tend to extend the ps lifespan.