New build problems

[punkrkr52]

so i recently built a computer for a buddy of mine. MSI K9N2G Neo-FD mobo, GeForce9600 GT vid card. heres the issue. when i plug the monitor into the onboard video card, everything boots up comes on screen no problem. but when the monitor is plugged into the 9600, the bios splash screen, and windows loading screen all show up, but as soon as it gets into windows, the screen is just black. all the connections in on the mobo and vid card are good, so i figure its drivers. install the latest drivers, and nothing happened. did a windows update, installed drivers, and nothing. i try his vid card in my roomates computer (who has the same mobo and vid card) and it worked. So i put it back into his case, and wouldnt do anything. so i rolled back the drivers to the ones that came with the mobo, and everything worked. i restarted it twice, and it was fine. about 20 minutes later he calls me and says that its going to black as it boots into windows like it did before.

Now i am very confused. I just built my roomate a nearly identical pc 2 weeks ago, and never had a single problem. i'm assuming its software, but i dono. do you guys have any ideas? something i didnt think of? i dont want to send anything back unless i have to.

[cauzomb]

If it's possible, set the bios to "disable onboard graphics" vga= pci-e and recall vga bios on s3 resume "enabled" ~this setting is needed to prevent the black screen on some cards, if you use standby or sleep mode but your graphics card driver needs to support the s3 resume function. Try to disable the onboard geforce 8200 in the windows hardware manager. Make sure that the monitor drivers are installed for the monitor that is showing connected to the 9600gt via the display properties advanced tab, and then set the correct color depth, resolution and refresh rate for the monitor's native resolution if it's an lcd, or a compatible refresh rate/resolution/color depth, if it's crt. you might have to boot into normal mode, with the 8200, install the drivers on the 9600, then plug the monitor into the 9600, if you get your desktop/display showing up when you plug into the 9600, open the graphics display properties, go to advanced, then in the monitor tab, check the monitor driver, if it says plug and play monitor, or default monitor, select change driver, then tell windows where the driver is ~get the driver etc... then go into the hardware manager and disable the 8200. What PSU did you use? Does the graphics card need it's own power tap, is it connected etc..

[punkrkr52]

i had tried all that all ready. the wierd thing about it all, is that it would sometimes work for a little bit, and then stop. it would work at post, but as soon as windows loaded it would be black.
i ended up taking everything apart and putting it back, and now everything works like a charm. confusing the crap out of me, but it works. i appreciate the help tho cauz

[cauzomb]

maybe a dirty connection; falty or loose power plug connection etc? If it starts doing it again, take a close look at the round molex female connections, they sometimes spread apart and make poor contact.