Abit BP6 / Video Card Problems

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I am having some serious problems with the motherboard (BP6) and my video card as well as sound card. It seems that every time I reboot the computer, my video card is no longer detected (the message reads "there is a problem with your display adapter") and then I click cancel on the hardware troubleshooter, and click "OK" to set it at 640x480 at 16 colors, then it reboots. Once it reboots, the card work is detected fine, but if I ever reboot again, I have to go through the same process all over again. At first I thought it was a problem w\ my video card (which was a Matrox Millenium), but it does the exact same to my new video card. The first card millenium was a PCI card, and my new card is a Matrox G400 which is AGP, and the problem does NOT go away. Not only is there a prob with the video card, but also my soundblaster live as well, which stops being detected along w\ the video card and I have to remove it from device manager, and then refresh to get it working again........ Please help me out I am going crazy here and can't figure out why this motherboard is doing this to me (I've tried reinstalling win98 SE about 5 times already) (clean installs too.......).
I need to get this worked out or I will be forced to replace this motherboard.

Here are my system's specs:

Abit BP6
Intel Celeron retail 466mhz
128 megs PC100 RAM
Matrox Millenium G400 (AGP)
SoundBlaster Live Value (PCI)
Adaptec 2940UW SCSI (PCI)
10/100 Base-TX generic Ethernet Card (PCI)

attached to the SCSI card:
Yamaha CDR400T (Scsi)
Toshiba 40x SCSI CD-ROM (Scsi)
Quantum Fireball ST (Scsi)

attached to the primary IDE onboard controller:
Maxtor HD
Quantum HD