Picture shuttering while playing game

[Junaid Army]

Guys I'm getting an strange problem that when I am playing any game I get micro shuttering specially in latest games like FAR CRY 4 and Assassin's Creed Unity,, but when I checked my thundermaster utility the GPU wasn't at all over-clocked but still there are shuttering and this problem I was getting over a week ago, now it seems to be I can't play any game because of an error which pops up from taskbar "Display driver has stopped responding and has recovered", none of the games runs and weather the game will crash or it will be showing BSoD like "Your PC ran into a problem and needs to be restarted", now my friend I want to know weather it has any problem with the graphics drivers or it is something hardware related problem?? My people told that GT 630 1GB GDDR5 will not be able to handle new games and may over heat and damaged mother board or anything else. Now for that I thought to get a GTX750Ti 2GB as a Christmas gift for me but when I went to shop they told me that my SMPS (PSU) won't meet the recommend watt but mine is 450 watt I think it should handle it now I am so sad that even before I could play the game but nowadays I can't even play them. My budget is about 235$ and please suggest me a GPU that is good at my budget but before, tell me that will I be able to recover my GPU or need to buy a new one and my PC specs are given below :

CPU: AMD FX(tm) 6300 3.50 GHz (4.1GHz turbo)
RAM: Corsair valueset 8GB DDR3 (1600 MHz)
GPU: Palit Geforce GT 630 1GB GDDR5 (which I am thinking to replace with a good one)
HDD: WD Cavair Blue 500GB
PSU: antec 450 watt 20A SMPS
MOBO: Gigabyte Ultra Durable series motherboard

 

[vrumor]

A 750Ti should work just fine on your PSU. As for your budget, if you went with a GPU that requires a 6 pin or 8 pin or both, youd have to upgrade your PSU.