I have this weird problem and maybe some of you have encountered something similar.
I restarted my PC today, and upon booting up, I'm greeted by an error message about the power plug for the video card not being connected and loud beeps from the motherboard. So I check all the connections and power up again, but still the same error. Wanting to avoid the hassle of switching out cards, I first try plugging the monitor into the secondary DVI port, and guess what... the system boots up fine.
I'm using the analog connection for my monitor with a DVI to analog converter (card only has DVI ports) so I think to myself "Maybe the adapter went bad for some reason". So I try another adapter but the same thing happens; one port works while the other doesn't.
So now I try using a straight DVI connection. Reason I don't use it is because for some reason the GRUB menu doesn't displey with a digital connection. Anyway, using a DVI cable I can get both ports to work perfectly . So now I'm confused. The DVI ports on the video card obviously work, so why would trying to use an analog connection stop the whole PC from booting up?
To recap, DVI connection work, while analog connections only work on one port. Could it be the video card itself? Maybe the motherboard is receiving faulty signals? I already tried a different monitor and the same thing happens.
It's not an OS problem, but more of a hardware thing. The PC does not even boot up. The only thing it does is display the error message and beep continuously (1 second delay). Only an analog connection does it on one of the DVI ports, but a straight DVI connection works fine on both ports.
It's really confusing, because if it was one of the DVI ports on the card that went bad noting would work with it. It's not the monitor because the spare screens I have do the same thing. I doubt it's the card, because I've been using it to play games all day with no problems.
You think it's the MB? I have been having problems with it recently, like the BIOS becoming currupted for no apparent reason (I rebooted the PC and was greated by a "bad checksum" message on the BIOS). Further still, my old X1950XT died on me in a similar way.
Is the beep the same as you get if no monitor is attached ?
When you say "I'm using the analog connection for my monitor with a DVI to analog converter (card only has DVI ports)" do you mean "DVI-I port, which includes analog pins, and a DVI-D to VGA adapter" or "DVI-D, with only digital outputs, and a specialty digital to analog converter" ? Sorry to nitpick, just trying to fully understand.
First guess is that for some reason the analog monitor is not being sensed on one of the ports (either analog load detect or EDID not being read properly) and that the computer does not boot as a result. Also depends a bit on whether the DVI-to-analog adapter asserts the Hot Plug Detect pin -- not sure what the convention is these days.
I'm very certain that the DVI ports on the standard HD2900XT are DVI-I, and the converter I'm using is the one that always gets bundled with cards. The monitor has both connections (analog and digital) so I can use both. Right now I'm using a DVI cable, so obviously the digital connection works fine (it's connected to the port that does not seem to work with the analog connection).
I really hope it's not the graphics card. This is the second I burn through with this same MB, so it could also be the MB that's killing the cards (last one died with similar symptoms). The video card itself seems to work fine, except for it not wanting to work with analog output on one of the ports (DVI works fine on both of the output ports).