My8rda+ hates my Radeon 9800 pro

I just installed a new 8rda+ Rev. 2.1 mobo a week ago. The first time i booted it up, I was able to access bios just fine, but when i hit F10 and rebooted, the video was dead! I removed all the PCI cards and tried again, and nothing. I checked to see if my 9800 Pro was seated properly, it was. I cleared CMOS and still nothing. So in an act of desperation I tried my Geforce 3 card. It worked perfectly. I tried my 9800P in my wife's computer and it was ok. When I tried it in my system again it still wouldn't work. I reinstalled the Geforce 3 again and tried the "reset configuration data" option and saved it, the shut down and installed my 9800p again. It worked this time, but every time I shut it down, I have to clear CMOS to get it to boot. I keep getting a 26h error code, which according to my manual is an overclock error. This happens even at stock settings. I am using the following:

Athlon X2100+ rev. b (can't remember the other stuff) Turtle beach Santa cruz sound card, US Robotics modem, Windows 2k SP2 and the on-board LAN is in auto. I have disabled the onboard AC97 sound. I have tried overclocking, stock settings, and even tried underclocking once to see if that would help. I have tried the insert key and that doesn't help much. I am back to using my Geforce 3 for now until I can figure this one out. My PSU seems to be ok. The 9800 Pro worked fine in my MSI KT 4 Ultra. This seems like an IRQ conflict or something. I once removed my sound card and it booted right up, but only that one time. After that I was back to square one. Any Ideas on this one? Is this problem common with this mobo? Any help would be greatly appreciated. Thank you.

Did you plug the 9800pro in like on one of the floppy power cables or whatever? Even so what power supply do you have?

Try your 9800 in your computer, but with your wife's power supply, or maybe even your wife's psu on the card, but your psu on everything else.

I did plug it in to the power supply four-pin connector, but even so, I received a red warning box during POST which flashed so fast that I could not read much of it, except that I needed to reset something. I have an Allied 450w PSU, because I was on a budget. I really prefer Enermax, which is what I put in my wife's system. I will test my system with her power supply and my R9800 and see what happens. I am not sure that the PSU I am using is all that great. It is an Allied AL-B455E. Thank you for responding.

I have that same issue when I first bought my 8rda+. It turned out that my old Crucial 256mb's wouldn't go together in slot 1 and 2. Used only 1 RAM stick and everything worked like a charm. Then I replaced it with 2x512mb Kingston HyperX.