Msi ati 4830 - blank screen

Yesterday I bought MSI 4830 512MB OC graphic card to upgrade my older pc (motherboard ASUS P5WD2 Premium, monitor CRT, AOC 9 with vga connector, old graphic c. ATI 800 GTO). I removed old GC and installed new one. But there was blank screen. I have tried to install my old x800 to second PCIe simultaneously with ati 4830. And I found out this: 1) 4830 doesn't work alone, but it work if there is second GC(monitor is connected to 4830). 2) after proper driver install, config, I removed old GC (monitor is connected to 4830) and it doesn't work - just blank screen, but i can hear that win xp is starting (and i can turn it off with button on my keyboard). Please help me !

I've found some solution. It's the matter of BIOS. 4830 can operate alone. After turning PC on, the 4830 is displaying nothing. I have to press Ctrl + Alt + Del to reset PC during POST. And miracle happens. GC is working fine. I must write to ASUS.