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macsforme

macrumors regular
Original poster
Mar 16, 2007
144
88
I am trying to update the CPUs on my 4,1 -> 5,1 dual-CPU Mac Pro. I bought a pair of these processors and used this delidding service to get them ready to install (this guy says he tests all CPUs before delidding to make sure they work, but I didn't otherwise test the processors myself). Prior to installing the new CPUs, I did the 4,1 -> 5,1 firmware update and installed High Sierra 10.13.5 (this included the firmware update MP51.0087.B00).

Screen Shot 2018-06-15 at 10.45.35 PM.png
I installed the two new CPUs and booted up the system. I got the startup chime, but this was the one and only time I got the chime with both new CPUs in, and also the only time the CPU in slot A showed any signs of life. I saw the Apple logo and progress bar for a few seconds, but it froze and wouldn't progress further. I did a hard shutdown, removed some PCIe cards and external peripherals, and attempted to boot the machine again. I got most of the startup indicators (power light, fans, hard drive spinning), but no chime and no boot up (also no CPU fault lights). As I was trying different things, I switched the processor in slot B into slot A and left slot B empty, and the machine did boot up a few times this way and showed the correct processor information, but I couldn't get the two processors to work together again. As I kept re-seating the processors and adjusting the heatsinks, I eventually saw the CPU 1 fault light (with the "good" CPU in it), and then the good processor never worked again.

I tried several times switching one or both of my old processors back in, and they worked every time. Ultimately I left the old processors in the machine and started using it again, and everything seems fine except an odd new issue where if you reboot the machine a few times (not a cold start), a few of the fans will go up to and stay at maximum speed, even though the CPUs are not hot... odd...

Screen Shot 2018-06-16 at 11.15.54 PM.png

At this point I don't know if:

1) The latest firmware update is causing some issues, or
2) BOTH of the new processors were faulty, or damaged during the de-lidding process (or installation), or
3) Somehow my power supply can't supply enough power to the higher-wattage processors, or
4) My Mac Pro is destroying processors

I tried every kind of reset I could think of. I even tried plugging the machine into a power receptacle in a different part of the house (based on this article), and still no luck. At this point, finding parts to swap in to debug this issue is going to be difficult and/or expensive. Any pointers?
 
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macsforme

macrumors regular
Original poster
Mar 16, 2007
144
88
Did you try to put the original CPU back in yet?
Yes, and everything seems to work fine with the old processors back in. As stated above, the fans were blowing hard after reboots sometimes, but after using it for a while I think that has already resolved itself.
 

h9826790

macrumors P6
Apr 3, 2014
16,620
8,554
Hong Kong
Yes, and everything seems to work fine with the old processors back in. As stated above, the fans were blowing hard after reboots sometimes, but after using it for a while I think that has already resolved itself.

Oh, sorry, I missed that paragraph.

If the original CPU works, the new one doesn't, Then I can only assume the new CPU are faulty.

For that delid service page. They said all CPU are tested before and after delid. And they can guarantee a refund. May be it's time to contact them. Ask how they test it, and how to get the refund.
 
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macsforme

macrumors regular
Original poster
Mar 16, 2007
144
88
I contacted the person who performed the delid service, and he suggested the CPU contact points may not be making good contact with the pins, so I should clean the contacts and the pins. I did wipe the contacts down with alcohol on a Q-tip, and blew the socket/pins out with compressed air already, but the pins are so fragile that I’m afraid to touch them with anything. Is there anything else I should try as far as cleaning them?
 

h9826790

macrumors P6
Apr 3, 2014
16,620
8,554
Hong Kong
I contacted the person who performed the delid service, and he suggested the CPU contact points may not be making good contact with the pins, so I should clean the contacts and the pins. I did wipe the contacts down with alcohol on a Q-tip, and blew the socket/pins out with compressed air already, but the pins are so fragile that I’m afraid to touch them with anything. Is there anything else I should try as far as cleaning them?

Never ever touch the pins on the sockets, don't even blow them unless absolutely required. And since the old CPUs work, that means the sockets themselves are good.

Try to clean the CPU is good enough (if suspect poor contact).
 

macsforme

macrumors regular
Original poster
Mar 16, 2007
144
88
To finish this story, I ended up buying a pair of x5677 CPUs for $30 apiece (rather than over $100 apiece for the x5690s) so I could see where the issue was. I popped them in briefly with the integrated heat spreaders still on to see if they would work, and the machine recognized both of them just fine. This time I delidded them myself, and I think I destroyed one of them in the process :(, but I ordered one more and was more careful delidding it and I now have two working quad-core 3.46GHz CPUs in my system. It's pretty late in the game now, but I will see if the eBay seller for the x5690 CPUs will take them back at this point (not sure if he will with the lids off, or maybe I can reattach them?) so I'm hopefully not out over $200.

Is it normal for these CPUs to be so fragile? Up until now I've hardly ever heard of a CPU failing.
 

kohlson

macrumors 68020
Apr 23, 2010
2,425
736
From your posts, I would say that you have a pretty strong case that the de-lidded CPUs arrived in non-working order. *You* have proven you know what you're doing by swapping back in the originals, and a completely different pair - and they work. It cannot hurt to contact the de-lidder and ask for a replacement or refund. You may want to cite a few threads here on MR! At any rate, you can rate him accordingly (super, for good service, or awful, for watch out). Good luck - keep us posted!
 

pl1984

Suspended
Oct 31, 2017
2,230
2,645
To finish this story, I ended up buying a pair of x5677 CPUs for $30 apiece (rather than over $100 apiece for the x5690s) so I could see where the issue was. I popped them in briefly with the integrated heat spreaders still on to see if they would work, and the machine recognized both of them just fine. This time I delidded them myself, and I think I destroyed one of them in the process :(, but I ordered one more and was more careful delidding it and I now have two working quad-core 3.46GHz CPUs in my system. It's pretty late in the game now, but I will see if the eBay seller for the x5690 CPUs will take them back at this point (not sure if he will with the lids off, or maybe I can reattach them?) so I'm hopefully not out over $200.

Is it normal for these CPUs to be so fragile? Up until now I've hardly ever heard of a CPU failing.
No, these CPUs are not fragile. To my knowledge the only thing which makes the dual CPU 4,1 difficult to upgrade is the 4,1's use of no lid CPUs which are, relatively speaking, hard to find. Use non-lidded CPUs and the upgrade is easy.
 
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