MP 6,1 Mac Pro 6,1 1st Red LED Flex Nightmare that led to two broken Mac Pro's

[GreppMichaels]

Hi Everyone,

So today has been an absolute nightmare, was upgrading a 6,1 to a 12 core d700 (4th time) and I'm guessing I fried the CPU riser in the process? I swapped out just about every other part (With the exception of the GPU and PSU) from a functioning 6,1 d300 to test what was and wasn't working and ended up swapping out the riser and it ran fine. I went back and started working on the now non working d300, reseated the 12 core, then reinstalled the 6 core, swapped out the logic board and flex cables a buncha times, and now I'm getting the red light on both my D700 and D300 (original culprit as I suspect it needs a new riser) but it looks in my troubleshooting parts I busted both mac pros.

This is an ultra bummer because I literally had a client coming by tomorrow (saturday evening) to pick it up, this is kinda how I make a living so I'm pretty devastated. What I'm hoping is in the process of swapping the logic board and the flex cables back and forth that I ruined some of the flex cables? I did notice a couple had some ultra minor bends in the pins, I've been trying to be careful but I'm guessing they aren't meant to be swapped around like I have been. With that said, even my d700 That eventually failed, used to atleast have the USB/LB/Hub area light up but it wouldn't boot, same with the original non-booting mac pro, but now neither of them are even doing that. Is it possible I trashed the connections on any of the GPU's as well? The connectors look clean, but again I'm guessing these things aren't meant to be plugged and unplugged multiple times. Also wondering if the CPU riser connector wears out easily too? I even cleaned it with rubbing alcohol.

Have I fried my logic boards? Have I trashed the flex cables and maybe the logic boards, both? The D700 Mac Pro literally went from working fine to non-working after I swapped its logic board and flex cables one more time. No idea how this happened, I've been working on 4,1s, 6,1's macbook pros, and PC's in general for years and I've literally never had an issue like this, its just absolutely devastating as at the worst I'm going to have to buy "new parts" but at ridiculous prices.

Anyways if anyone has any advice please let me know. Already ordered 3 new flex cables because it's atleast a simple solution and I'm hoping atleast on the D700 I just somehow trashed the cables, but I'm assuming on the D300 I need a cpu riser. Please advise.

 

[Koka016]

Nobody to help with advice?
Im in the almost same situation after 1 Unsuccessful 12 core Upgrade
I think I fried the CPU Board Mac pro powers on and beeps every 5 seconds like there is bad or no Ram memory
But Ram wasnt a problem Before Upgrade? No sturtup Chime at all just beep 5sec and Beep....
I will swap only Logic board I/O flex cable first from workong machine.
But Im afraid to swap a CPU board with CPU inside from working Mac pro 6.1 12 core to non working one.
Is it safe to check ? Did I lost CPU board or Logic board or both ? These are around 400$ US and more on ebay.
I have no diagnostics Leds on ?

 

[macguru9999]

Its pretty hard to answer these sort of questions without going through the troubleshooting process .... My limited experience was that I had one 6,1 with a bad riser(motherboard) and one with a cooked cpu. I took the riser from the second and installed a 12core cpu and reassembled and had one perfect 6,1 , selling the dud for parts. But I had the 2 machines so i could swap parts around.

 

[MisterAndrew]

Apple's technician's guide shows the correct routing for the flex cables.

 

[Koka016]

I hope Cpu Board is not dead because it beeps every 5 seconds?
Maby some slightly bent pins in socket I dont saw already?
What are your symtoms GreppMichaels?

 

[GreppMichaels]

No beeps for me, was able to get both my Mac Pro's fixed the other day, I ordered new GPU and IO Board cables, apparently they are very fragile, simple movement can break them. Koka016 I'm afraid to say your problem sounds like something with your memory/CPU tray, I know the beeping sound is supposed to be memory But do you know if you bent or damaged any transistors around the CPU? There is a service light that's supposed to have to do with CPU problems specifically, but maybe there is an issue with your CPU that solely pertains to the memory controller? My expertise lies more with 5,1's so sadly I don't have much more insight to offer.

The only other thing I can think of, is if you have unsupported memory, for example 32gb sticks won't run in the lower end CPU's, as I tested mine out before I upgraded to the 12 core. So my only real advice is to inspect anything on the CPU socket/board for damage, if you have a newer phone that has a good zoom feature you can use it to inspect the pins on your boad, I actually slightly bent one on an install and was able to bend it back with a lot of patience and a pair of very small tweezers, just be patient And careful.

If you do need replacement parts your best bet would be finding a mac pro that has bad video cards and trying to lowball as much as possible, use it for parts, and resell it or part it out. I think the used parts market will dwindle down as the prices of used 6,1's are starting to get almost as cheap as some of the parts, a similar issue with greedy resellers of cpu trays on the 4,1/5,1's so I'm hoping the used parts market catch up to reality. Good luck

 

[julik_tar]

Had this just now when replacing the heatsink - the LED turned out to... indeed mean that the cable is not seated!

It was not all the way seated in the interconnect board. A few swift moves with the spudger and we are again in business.