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MacVidCards

Suspended
Original poster
Nov 17, 2008
6,096
1,057
Hollywood, CA
While testing the new 4870x2 ROMs I booted into WIndows and played some Halo 2 for 5 minutes or so. When I was done as I started to exit Halo, the computer abruptly turned off. It had done this before with 4870x2 playing Crysis so I thought little of it.

I tossed a 3870 in to do some fiddling and it booted normally. I went to run errands and returned to wake machine from sleep. After a few seconds it shut down. I rebooted and halfway through boot it shut down again.

Now there is NO response from anything...the mighty Mac has died. There are no LEDs on anywhere when plugged in so I am hopeful it is the Power Supply. DVWharehouse has them locally for $280. Guess I'm getting one tomorrow.

Meanwhile, I think I may sell my 4870x2. It always seemed the Mac Pro was at the end of it's limits running the beast and perhaps the new 3.0 5160s in concert with warm weather and draw of 4870x2 were too much.

The card was powered via the 2 logic board connectors.

Does anyone have a link to the 2006/07 service manuals? Hoping there is a magic "reset button" but realistically.....not.
 
Try booting by placing the original restore disk in the cd drive, and boot while holding the "C" key. If the drive won't open, use a unbent paperclip to open the bay (you will have to hold the little cover down to access the hole to push the paper clip in. The BIOS in the computer should do the start-up procedure, though it may take a little longer to get it booting because it is using the CD.

Other than that, Im out of ideas.
 
From the Apple menu, choose Shut Down (or if the computer is not responding, hold the power button until it turns off).
Press the SMC_RST switch, which is located to the right and slightly below the row of diagnostic LEDs. Press the power button to start up the computer. Or, you can reset the SMC by removing AC power:
From the Apple menu, choose Shut Down (or if the computer is not responding, hold the power button until it turns off).
Unplug the AC power cord. Wait at least 15 seconds. Plug the power cord back in, making sure the power button is not being pressed at the time. Press the power button to start up the computer
 
Bad RAM Riser? YEAH !!!

x2 still not a go but I haven't reflashed the Slave back to original

The Mac was dead to the world, not a glimmer of an LED to give away trickle current, no response whatsoever to pushing the "on" button, etc.

I started yanking the RAM boards and noticed when I pulled the lower one a red LED lit briefly on the logicboard.

First sign of life in hours.

Turns out that Mac will boot and run normally as long as RAM riser is out.

If I insert it and try to start....back to DOA. So something on riser seems to be a dead short.

I yanked it out and in the darkness it appears some traces have melted/lifted /shorted. There is also a choke coil that looks a little dodgy but I am fairly certain these are bad traces in pic.

Funny thing is that board had the piddly 512 sticks the machine came with, 4 of them in total.

The other RAM riser has 2 @ 2 Gigs and 2 @ 4 Gigs for a total of 12Gigs. Dead tray had but 2 Gigs total among 4 sticks.

If I move the good one to lower slot everything still works fine. So it appears I got really lucky and only burned up a RAM riser...though still not sure how I did that.

I'll update when I get a new one.

Wheww !!!
 

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What happens when you push the diagnostic button on the logic board under the RAM?

Do you get trickle power?

Do you get regular power with the button and the power button?

There is a row of diagnostic LEDs!

I can mail you the PDF I got from Tess if you give me an email.
 
btw, just a tip for when you get it back
i think ram must be paired in mirrors...
like, riser A should be mirrored to Riser B
that means in first 2 slots of both risers you should have 0,5gb sticks, and so forth..
also heat dispersion (IN THEORY) is more even that way..
ccheeerss
 
btw, just a tip for when you get it back
i think ram must be paired in mirrors...
like, riser A should be mirrored to Riser B
that means in first 2 slots of both risers you should have 0,5gb sticks, and so forth..
also heat dispersion (IN THEORY) is more even that way..
ccheeerss

what about my pro when it shipped with 1gb, two x 512mb sticks both in riser a :p

now i have:
A 1 1 .5 .5
B 1 1 0 0

the later models have different setups but 06/07 you do it in pairs.
 
x2 still not a go but I haven't reflashed the Slave back to original

The Mac was dead to the world, not a glimmer of an LED to give away trickle current, no response whatsoever to pushing the "on" button, etc.

I started yanking the RAM boards and noticed when I pulled the lower one a red LED lit briefly on the logicboard.

First sign of life in hours.

Turns out that Mac will boot and run normally as long as RAM riser is out.

If I insert it and try to start....back to DOA. So something on riser seems to be a dead short.

I yanked it out and in the darkness it appears some traces have melted/lifted /shorted. There is also a choke coil that looks a little dodgy but I am fairly certain these are bad traces in pic.

Funny thing is that board had the piddly 512 sticks the machine came with, 4 of them in total.

The other RAM riser has 2 @ 2 Gigs and 2 @ 4 Gigs for a total of 12Gigs. Dead tray had but 2 Gigs total among 4 sticks.

If I move the good one to lower slot everything still works fine. So it appears I got really lucky and only burned up a RAM riser...though still not sure how I did that.

I'll update when I get a new one.

Wheww !!!
Ouch! It looks like the finish may have been HASL (Hot Air Solder Leveling), got too hot, and bridged. :eek:

Have you tested the memory on the dead riser to make sure they didn't get taken out?
 
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