Need Help disabling onboard graphics on Biostar P4M900

[ROLFWOLY]

I just finished building my computer and am trying to install a 512 MB Nvidia 8800 GT on a Biostar P4M900 Socket 478 Motherboard. My computer meets all the required specs for the card, and I am almost 100% certain that I installed it right. I disabled the onboard vga display in device manager and uninstalled the drivers for it. I looked in the Bios for an option that would disable the onboard vga, but couldn't find any.
When I hooked the monitor up to the video card and turned on my computer the display wouldn't come up and I didn't get any POST signal. I tried to get help from Biostar online for disabling onboard vga in the bios, but they don't have hardly any of their tech support files on their USA site.
Does anyone have a P4M900 motherboard or know whether or not I have to disable onboard display in the Bios for this motherboard to install a new graphics adapter? If so, it would be great if you let me know.

[Zenphic]

Go under "PnP PCI Configurations" and then "INIT Display First". Change it from "Onboard" to "PCI-E". That might do the the trick.

[Adrian Wong]

Most motherboards should automatically detect the presence of a separate graphics card and disable the onboard graphics. But it's a good idea to disable it in the BIOS anyway.

Check this page out for more details - Tech ARP - Init Display First

[ROLFWOLY]

Unfortunately I set the "Init Display First" to "PCI-Ex" and didn't get any different results. Thanks for the helpful suggestion anyways, though.
Under "PnP OS" do I need to set it to "Yes" when using Vista or will that not affect hooking my monitor up to the new Graphics Card?

[Adrian Wong]

Originally Posted by ROLFWOLY

Unfortunately I set the "Init Display First" to "PCI-Ex" and didn't get any different results. Thanks for the helpful suggestion anyways, though.
Under "PnP OS" do I need to set it to "Yes" when using Vista or will that not affect hooking my monitor up to the new Graphics Card?

For Vista, you should disable PnP OS. Details here - Tech ARP - PNP OS Installed

Regarding your problem, did you update the BIOS yet?

[ROLFWOLY]

I updated the Bios for my motherboard and I'll change the Bios setting on "PnP OS" back to "No." I still keep getting the same results.
I read on another online forum that someone had posted basically the same thing I did. They bought the Biostar P4M900 and an 8800 GT and are having the same problem that I am. I don't know if maybe the motherboard just simply can't support a high-end graphics card even though it has a PCI-Express x16 slot. If this is the case then trying to get a "bargain" motherboard with a PCI x16 slot was a bad idea, and I'd really hate having to pay for a new motherboard.
I know there is probably not much more help anyone can give, but if anyone has anymore suggestions they would be greatly appreciated.

[The_YongGrand]

Originally Posted by ROLFWOLY

I just finished building my computer and am trying to install a 512 MB Nvidia 8800 GT on a Biostar P4M900 Socket 478 Motherboard. My computer meets all the required specs for the card, and I am almost 100% certain that I installed it right. I disabled the onboard vga display in device manager and uninstalled the drivers for it. I looked in the Bios for an option that would disable the onboard vga, but couldn't find any.
When I hooked the monitor up to the video card and turned on my computer the display wouldn't come up and I didn't get any POST signal. I tried to get help from Biostar online for disabling onboard vga in the bios, but they don't have hardly any of their tech support files on their USA site.
Does anyone have a P4M900 motherboard or know whether or not I have to disable onboard display in the Bios for this motherboard to install a new graphics adapter? If so, it would be great if you let me know.

We need to know your PSU first - and usually running a PCI-E on 20-pin power system isn't helping the PCI-E gfx card properly. Also, we must need to know the PSU details too. I may be wrong here - any opinions?

Also, putting an 8800GT to that Socket 478 (i guess yours must be a Pentium4) is a serious bottleneck. jmho.

[Adrian Wong]

Oh wait.. It's a GeForce 8800 GT. Did you attach a 6-pin power cable to the card?

[ROLFWOLY]

I made sure to attach the 6-pin power cable from my PSU every time I installed the card. I even tried using the 6-pin PCI express to two 4-pin Molex adapter.
My PSU is a Thermaltake 500W with a combined 12v rating of over 30a, which is what the 8800 GT requires.
Updating my bios caused my system to start acting very erratically, so now I have start over from the beginning by restoring the bios with a floppy disk. I backed up the bios in the flash program but I can't even get Windows started. Hopefully once I get my bios restored I'll hear back from Biostar tech support on exactly what needs to be done to make my card work.
I still would appreciate anymore suggestions on trying to install the card or even suggestions on what would be a good buy for a replacement Socket 478 motherboard (If such a thing exists). I would really like to keep my CPU and CPU Fan.
Once again, Thanks for all the help.

[Adrian Wong]

Hmm.. That's odd. BIOS updates generally improve reliability, not the other way around.

To restore the old BIOS, you will need to boot up with a DOS boot disk.

From what I can see, it looks like a motherboard issue. Nothing to do with the PSU or the graphics card.