MP 7,1 No error lights, but 7,1 won't send image to external monitor?

[Grumply]

Hi guys,

I've started tearing my hair out. So figured I'd check with the Hive mind. I've just got home after 6 weeks overseas, and my 7,1 is refusing to boot. Or at least, if it is booting, it's refusing to send any kind of image to an external display through either one of the two 6800XTs that I have installed.

I've tried SMC resets, and I've tried PRAM resets (the PRAM resets don't appear to be working though - they don't restart the machine). I've tried switch out monitor cables, and tried the monitors individually (from each GPU).

I've removed every extraneous PCI card, and every external peripheral. But still no change.

The machine boots up. I get my solid white light on the case, but no image to any monitor I plug in. The GPUs fans also appear to start up when I turn on the machine, but then they stop.

I've tried removing and re-seating both my RAM and the CPU, but neither has changed anything.

I don't know what else to try at this point. Any suggestions?

 

[Grumply]

I've just tried bypassing the housing so I could inspect the diagnostic LEDs on the motherboard. I'm only getting the first two lighting up. According to the service manual this suggests that power is getting to everything, but the CPU isn't starting the boot process.

 

[4wdwrx]

Some ideas:

With the original MPX video card do you see video?

Also, tried different video output ports on the video card?

 

[Grumply]

Some ideas:

With the original MPX video card do you see video?

Also, tried different video output ports on the video card?

I don’t have the original 580 MPX module anymore.

I’ve gone through the diagnostics troubleshooting to see which hardware components might be faulty, but I’m stuck at the RAM.

Every single DIMM (I have 12) is creating the Memory Warning Light to flash (I’ve tried them all individually).

I’ve never heard of that many DIMMs going bad at the same time. What else could it be?

 

[4wdwrx]

Try the original Apple DIMMs if that is not what you have.

Is the Mac plugged directly to the wall? or UPS/extension, which may be faulty reducing power output.