D975XBX2 won't reset video if two monitors plugged in?

Geodesic · Post by **Geodesic** » Wed Feb 07, 2007 11:35 am

I've got a D975XBX2 (505) and a GV-RX195P256D-RH (ATI X1950) video card.

If I have monitors plugged into both DVI sockets on the video card, the mobo BIOS doesn't seem to be able to initialize video (no POST video), and boot halts. If I turn off the computer, unplug one of the two video cables, and turn the computer back on, video resets fine, POST shows up, etc.

In fact, if I unplug one video cable from the back of the video card just long enough for POST to initialize video, everything works great after that and I can plug in the other video cable.

Is that weird or what? Since I run a dual-head setup, and having both heads plugged inprevents boot, this is kind of a big deal to me.

Futzing with bus and video settings (what little there are in the BIOS) have made no difference.

Any ideas?

Intel D975XBX2 (505) mobo, bios 2507
Intel Q6600 CPU
Gigabyte GV-RX195P256D-RH PCIe video card
2x Patriot PSD21G8002 1GB PC26400 DIMMs
2x WD 500GB HDs on the Marvell controller

-Bryan

aleph6 · Post by **aleph6** » Wed Feb 07, 2007 5:47 pm

Do you have the extra video power supply connector plugged into the motherboard? If not, that's something pretty easy to try. I can't imagine the card draws much power idling, but it's something to try. That card does draw something like 125W under load according to one posting I saw on the net.

werty316 · Post by **werty316** » Wed Feb 07, 2007 9:15 pm

Have you tried switching the connections on the DVI outputs?

Geodesic · Post by **Geodesic** » Thu Feb 08, 2007 10:13 am

werty316 wrote:Have you tried switching the connections on the DVI outputs?

Thanks werty316 for your reply.

Yeah I've tried that. It boots if a monitor is connected to exactly one output (either one). It also doesn't matter whether the monitor that is connected is digital or analog (i.e. analog cable plugged into a DVI-to-VGA adapter).

Weirder still: restarts work ok. It seems to be POST that is dying.

On a cold start, I can disconnect one monitor, power up, and as soon as video is initialized, plug in the second monitor and everything's great. I can even Restart Vista and the restart will work, even with both monitors connected.

I'm inclined to think that it's a BIOS thing, but I'm going to try aleph6's idea too. Will report back in a few.

-Bryan

Geodesic · Post by **Geodesic** » Thu Feb 08, 2007 10:48 am

aleph6 wrote:Do you have the extra video power supply connector plugged into the motherboard? If not, that's something pretty easy to try. I can't imagine the card draws much power idling, but it's something to try. That card does draw something like 125W under load according to one posting I saw on the net.

Thanks aleph6 I just now tried that and it didn't help. I assume you mean the four-pin power block that looks like the kind on PATA drives. I didn't have it plugged in before, but now I do, and sadly, it still won't boot if two monitors are connected.

I tried another experiment too: Will it boot if a monitor is connected but powered off? Answer: nope. I tried booting with one of the two monitors powered off, and with both powered off. Perhaps DVI cables indicate connection via a two-pin short -- I haven't looked at the DVI pinout.

This is too annoying -- I'm running out of ideas. I guess I can just leave the computer on...

-Bryan

TomV · Post by **TomV** » Thu Feb 08, 2007 11:10 pm

I'm having the opposite problem.

If I do a restart, it hangs. So I turn it off, wait a few seconds, power back up, and it boots fine.

I have 2 DVI LCD's connected to a Gigabyte card.

But this is the only problem I've had during the first week for this MB and new build.

Intel BadAxe2 MotherBoard
Intel E6600 Processor
Corsair XMS2-800 Memory (1GB x 2)
Gigabyte 7600GT Video Card