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Hello everyone. Recently bought a dual 4.1, already flashed to 5.1. For the moment only studying and planning the CPU upgrade.
I wanted to ask, if anyone tried the Apple Technician guide "method", using a torque screwdriver with the mentioned .452 Nm torque for the first tightening and .904 Nm to secure screws. (p 160, 165)
 
CPU B Upgrade Problems

Ho Guys,
I'm having terrible problems performing the CPU upgrade to my Mac Pro too.
I have spent two days solid trying to sort it out but so far without any success.
It's a Mac Pro 8 core 2.26 i'm updating, already upgraded to 5.1 firmware and my problems are very similar to those experienced in this thread by CASLondon.
For me though it's CPU B that's giving me all the grief.
CPU A installed and booted up after about 3.5 turns each and all RAM in the slots (12GB) recognised.
Only took me half an hour to get to that point, so hopes were high that's I'd be done and dusted in about an hour - how wrong can I be.
Two days later and I still can't get CPU B to spring to life.
I either get blinking white lights, solid white light, or solid white light with red (CPU?) light. Its very difficult to see what Red light is coming on as it's located behind the processor (grr)!
So far I've tried swapping processors to check one isn't a dud and both boot up in CPU A fine.
However when I try B...no dice. :(
I have checked the socket under an LED lamp and magnifying glass and can see no bent pins.
I've tried installing just Processor B, but I go from simply blinking white light, solid white or solid white with Red light...SO frustrating. I've been doing the HEX screws in the heat sinks in increments of 10 minute segments on a clock.
Any advice I'd be very grateful for.
Thanks
 
Okay this is weird.
Right Now I've got in booting up (with chime at the start) and both CPU's in but only CPU A showing up. Nothing on the CPU B board is currently recognised including the RAM, so I'm currently a 6 core 2.93 with 12GB RAM, instead of a 12 core 2.93 Ghz with 24GB RAM.
What's bizarre though is I have no racing fans which I was getting when CPUA only was installed.
Definitely something not right about CPU B. :(
 
Not trying to hijack this thread but tell me this kind of torque drama is not going to happen with a single hex core that has the CPU casing over it...right?
 
Okay this is weird.
Right Now I've got in booting up (with chime at the start) and both CPU's in but only CPU A showing up. Nothing on the CPU B board is currently recognised including the RAM, so I'm currently a 6 core 2.93 with 12GB RAM, instead of a 12 core 2.93 Ghz with 24GB RAM.
What's bizarre though is I have no racing fans which I was getting when CPUA only was installed.
Definitely something not right about CPU B. :(

I had something similar when I did the exact same upgrade about 6 months ago. I ended up removing CPU B completely and restarting its install from scratch all over again, making sure to turn each bolt the required number of turns + a tad more (maybe 1/8th of a turn). That did the trick for me. The MacPro has been running without issues since then.
 
I had something similar when I did the exact same upgrade about 6 months ago. I ended up removing CPU B completely and restarting its install from scratch all over again, making sure to turn each bolt the required number of turns + a tad more (maybe 1/8th of a turn). That did the trick for me. The MacPro has been running without issues since then.

That's reassuring - thanks. :)
I think I'm going to reinstall the original chips and just check everything still works.
I've reinstalled the new chips about 6 or 7 times now and keep getting the same problem with CPU B and have reached the point were I'm giving up.
If the original chips work then all is not lost, but it's such a laborious process when it doesn't that it savages your spirit! :(
 
That's reassuring - thanks. :)
I think I'm going to reinstall the original chips and just check everything still works.
I've reinstalled the new chips about 6 or 7 times now and keep getting the same problem with CPU B and have reached the point were I'm giving up.
If the original chips work then all is not lost, but it's such a laborious process when it doesn't that it savages your spirit! :(

Hey, are you 100% certain that they are X5xxx chips and not W3xxx versions?
 
Hey, are you 100% certain that they are X5xxx chips and not W3xxx versions?

Yes, that's about the only thing I am certain about now.
I know longer know, who I am, where I live or what my name is I'm so bloody confused! lol

I think this upgrade is a little more serendipitous than it seems, which is why for (the fortunate) some it's been easy and for others like me it's been a bit of a nightmare.
 
Not trying to hijack this thread but tell me this kind of torque drama is not going to happen with a single hex core that has the CPU casing over it...right?

Naw you'll be fine. I have swapped processors in my Hex (formally Quad) 4,1 4 times and its running fine. The processors came from the factory lidded and it uses the standard processor latch system. The 4,1 Octos are a weird breed, someday I would like to get a Octo proc tray though for my system.
 
Success

Added down turns for a while on CPU B, and....

BOOT - dual x5680, 24g ram, geekbenching 64 bit over 30,000. Whoo hoo.

After geek bench finished, the fans started running hard and still are. Is that normal, or a sign of something? I gave it 5 minutes of fans, then put it to sleep manually

I need to fill the last ram slots and stress test this beast I assume, and add fan/temp/stat monitoring software. Suggestions?


What I've just started running into in my build is that I can get the system to boot off of CPU a and it will recognize all ram for first CPU but as soon as I get CPU b to the "point when the system sees it's there" turn wise (aka where I think it's just tight enough) the system will almost instantly shut off after the power button is pressed. Like power light hard drive spinning fans spinning and sec later it stops itself entirely. And I've tried all different amounts of backing off the turns (which then boots the system with 1 CPU) and more turns where the system just remains at the state of instant turn off upon power press.
Any ideas anyone. I'm going insane .Just spent 4 hours on just different turn amounts.
 
What I've just started running into in my build is that I can get the system to boot off of CPU a and it will recognize all ram for first CPU but as soon as I get CPU b to the "point when the system sees it's there" turn wise (aka where I think it's just tight enough) the system will almost instantly shut off after the power button is pressed. Like power light hard drive spinning fans spinning and sec later it stops itself entirely. And I've tried all different amounts of backing off the turns (which then boots the system with 1 CPU) and more turns where the system just remains at the state of instant turn off upon power press.
Any ideas anyone. I'm going insane .Just spent 4 hours on just different turn amounts.
Dual CPU on a 2009 Mac Pro?
If so, have you delidded the CPUs?
If you haven’t, then go and buy a cheap vice and delid the CPUs. It’ll take you 5 minutes and it is the correct way of doing things.
 
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What I've just started running into in my build is that I can get the system to boot off of CPU a and it will recognize all ram for first CPU but as soon as I get CPU b to the "point when the system sees it's there" turn wise (aka where I think it's just tight enough) the system will almost instantly shut off after the power button is pressed. Like power light hard drive spinning fans spinning and sec later it stops itself entirely. And I've tried all different amounts of backing off the turns (which then boots the system with 1 CPU) and more turns where the system just remains at the state of instant turn off upon power press.
Any ideas anyone. I'm going insane .Just spent 4 hours on just different turn amounts.

I think with all this so many turns on each corner of CPU heatsink to obtain good contact is pure folly, and a lot of CPU sockets are getting damaged in the process along with CPU's.

There are 2 ways of doing it, you either delid the CPU if your installation requires it, or you buy yourself some shim washers if your not able to delid or don't feel confident doing so. Measure hight of the original CPU using a vernier gadge against the new CPU subtract the difference and you have your shim washer thickness requirement. You can't use standard washers as they are stamped out and are not flat and have high edges.

It seems its hit or miss with this torque on each corner of CPU heatsink to get it to work, plus you could be wasting $ on broken sockets and damaged CPU's shim washers are cheap.

https://www.accu.co.uk/704-shim-was...MIp_6NlLuj3QIVaLHtCh3fEg8eEAAYBCAAEgINpPD_BwE


just one place to obtain them, and many more via google.
 
Dual CPU 4,1tryibg to upgrade to x5690. Delidded already and did both the exact same way.
 
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