Problem with my graphic card or mobo

Hey, i am new to this site and my friend recommend this site for help on computer stuff.

I just recently build a new comp, after I installed everything that I needed and use. While playing some games I got the Blue Screen of Death and it said something like Nv4.disp.dll, and STOP: 0x000000CF, 0x0000007E and few others i that forgot at the moment (Not all of those happen at the same time but all at different times). I researched these problems and try all the solutions that i found to fix these it~ I dont know if it could be my mobo or my graphic card problem. But from the finding I researched said it could be my Graphic card but I really doubt that its the graphic card problem. because before completing the new comp I did tested out that new graphic card in my old comp before i completed gathering all the other PC parts and it ran smoothly. After putting the new comp together i start getting these issues I dont know why~(the BSoD) I trying putting my new graphic card into my old mobo played some games and trying stressing it as much as I could at that time and works perfectly fine no BSoD or any other errors. so I try putting my old graphic card into my new mobo and did the same thing. Nothing happens sooo I am completely confused at this point. I dug more other ways and with some help of my friends, trying some more solutions on fixing my problem that i have~ we got Nothing... Soo at this point I would think this could be hardware problem between the Mobo and the graphic card. But for me I am saying its the mobo problem if you guys have any solutions or opinions to help it'll be great. PLEAS!! and THANK YOU!!

I am very sorry, if this is in the wrong post I dont know where to post this but in the end it does sounds like a hard ware problem.

New Comp Build:
Intel E8400
XFX 750i mother board
Sparkle GTS 250 1024MB DDR3
OCZ SLI-Ready Dual Channel 4096MB
WD 800GB
Ultra 650watt power supply
OS:Windows XP (32-bit)

 

Nv4disp.dll belongs to the nvidia drivers

I would strip all Nvidia drivers and related files from the System and then reinstall the Nvidia drivers and see if that helps.

 

Well did like uninstall most of it back then think, and did reformatted the comp a few times and before i decided to post this problem up. but ill still try it again.