Pc booting problem due to graphics?

I have an AMD athlon XP 1800+(palomino) on N-force based Asus A7N266-vm motherboard with onboard graphics(award phoenix bios etc), 512 MB DDR RAM(kingmax DDR-400).power supply is 400W (powersafe) Additionally I have the following components 80GB HDD,a graphics card(leadtek 6600LE with 256 MB RAM), samsung 740n MONITOR, DVD ROM,Combo Drive and DVD Writer (recently added).

Since last six months I have been facing problem with agp display card.

THE Screen would go blank after some time of usage and monitor LED would keep on blinking.After reboot it would work properly for sometime.Hence I had switched back to on-board graphics.I did this in Bios by changing the primary VGa BIOs(setting inside PCi configuration tab in BIOS) to onboard graphics.

The same problem recently occured while working on-onboard graphics, the PC froze .Since then my pc on powering up shows blank screen with the hard disk led continuously on.On two occasions I heard one long beep and 2 short beeps indicating a graphics memory problem.how Do I get to change to AGP graphics?(suggest keyboard combination since the screen does not show anythihg regardless of whether the monitor signal input cable is connected to either of vGA ports on the back). I Tried removing the battery and shorting the terminal to reset bios

Where could the problem be? Power supply? motherboard graphics? Ram?.

IF any hardware is faulty should I just replace that particular part or should I go for upgrade?(which means that I will have to dump/waste other components that are working properly)

please help.

Pc booting problem due to graphics?

the only thing i can think of is that there was a graphics driver error due to having the onboard graphics driver as well as the leadtek graphics card drivers not being uninstalled...i had a smiliar problem when i changed my graphics card out without uninstalling the drivers for the previous one.

Pc booting problem due to graphics?

It could be becoz of virus or some boot files are corrupt or anti-virus loaded in pc takes time to scan the system or the system needs clean-up by cleaning the temp files and cookies in system.

Pc booting problem due to graphics?

if your harddisk led is continiusly glowing then your motherboard mosphet chip is gone, you have ot replace the mosphet.

Pc booting problem due to graphics?

Upgrade your graphic driver