Windows won't load

my system specs are

CPU: Intel core i5 2.6 Ghz quad
GPU: NVIDIA GeForce GT 330, 2 Ghz
OS: Windows 7 64bits
Ram: 4 GB
DirectX 11

I played Dota 2 for 1½ years with no problems.
but starting from last month, my OS got some problem. dont' know what caused that.
My system become extremely slow after a few hours of Dota2. Right-click on the desktop takes like 30 sec to show pop up menu.
But sometimes its normal, like nothing happened. One day, it was drop dead, BSOD. after that windows refused to load.
Luckily there's an option to do system restore from the boot menu. and then computer back to normal again, for like 2 weeks.
And 2 days ago, it became super slow again. And then windows never load at all.
On the loading process, it says "windows is attempting to repair . . . . . ", "windows is trying to load the necessary files . . ." .
That took 3 hours and nothing happened.
I thought "ok its enough, can't wait". So I go and buy a new computer.

The new system specs are
CPU: Intel Core i7 3770, 3.4 Ghz quad
GPU: Nvidia Geforce GT630 2GB
OS: windows 8 64bits
Ram: 16 GB

First night I installed steam and dota2.
Second night I played 1 game, 40 minutes later, whoosh, the screen flickers. and then drop dead.
But this time, I managed to read the error message before the coumputer shut down itself.
VIDEO_TDR_FAiLURE @#$&^%$#@
and then windows didn't load at all. That make me rage, made me wanna kick all the things near me.
On the loading process, it shows "windows is analysing . . . . " message shows up.
It took 45 minutes, and then I pulled the plug.
After that I tried to ON the computer again, it took half an hour loading and do the windows update.
Luckily then start screen showed up.

I haven't done anything yet, except from updating latest GPU drivers after the incident.
I didn't know where to post this thread, Hardware, Gaming or software. Since it is the OS related problem, I post it here.
I wanna know what caused the problem, both computers have same source of problem or just a coincedence? Please kindly help.

 

Just FYI your post was moderated as you used ... in your post, which activates the spam filter. I would suggest that you attempt to avoid this in the future.