Busted graphics card

My graphics card which is Nvidia Palit 9400GT super 1GB is not functioning anymore. I noticed the problem earlier, I mean its still under the 1 year warranty. I had it checked at the Nutech Emall shop where I bought the PC unit. After 1 week of waiting for replacement (which I thought they replace it with a new one), they told me there were no problems with my unit, so they gave it back to me. For quiet a while I thought it was already okay, but sometimes I still experience the defect and sometimes it fixes itself (I mean it just turn okay after a long rest period). Recently after vacation, I turned on my PC and its not working anymore, I decided to have another shop check it, and they told me I have to buy a new one. And now Im saving to buy a new one, but Im kind of upset and regrets that I bought a PC from that shop.