Motherboard beeps once after graphics card installation

[toxict51]

hey guys, i bought a 9800gt green about 3 months ago and to be honest i have never been relaxed with it
from the day i bought it its just frequent blue screens 3-5 secs into windows logo.
and after i installed it the motherboard beeps once and then starts, at first i thought some motherboard do that to show its a normal post but i removed the video card and inserted my old 9400gt and the motherboard did not beep and the pc turned on perfectly fine
i later put back the 9800gt and the pc beeps and blue screen error(0x0000007E)the one that says make sure u have adequate disk space and so on. but after the BSOD i restart the pc and it works fine again
im confused here oh yea btw this green edition has a 6-pin which is very very weird.
so is it the graphics card thats faulty or that its not receiving enough power from the psu
my system specs:
Intel core2duoE4400 2.0GHz
NVidia Geforce 9800gt green
3GB DDR2 ram
Intel D940gzis motherboard
and i my psu bestec it has 500W and 12V 17A
i know it sucks
so what could be the problem?
do you think that its not reveiving enough power?

 

[ChiefTexas_82]

Is your PSU multi-rail? 17A seems low for a single. If it isn't a multi-rail PSU the 17A may not be enough to run that card plus the processor, fans, ...ect. If your PSU is multi rail with 2 or more 12V rails it should be fine.

 

[toxict51]

ill check if its multi rail now and report back
but what about the BSOD and the beep?

 

[toxict51]

edit:no i just checked it out and its not multi rail but the pc runs fine with the psu. i mean yesterday i just played 7 hours on the pc and no crashes what so ever, so i doubt its the psu. so what could it be?

 

[geekapproved]

Sounds like psu to me. PSU can definitely cause bsod's.

 

[toxict51]

yea i figured that much so u think that if i change my psu the bsod will be gone and the graphics card beep will stop at startup?

 

[toxict51]

oh and btw if it were the psu dont u think that games should crash ? but mine dont i mean crysis 2 ran 5 hours yesterday online and singleplayer no crashes no nothing.
i doubt its the video card, im guessing either psu or HDD im formating my HDD now performing a clean installation of windows 7 and ill report back if this did not work than ill change my power supply