4,1 CPU Upgrade -> Fans racing, CPU B's fan or thermal diode not detected

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Hello folks! I was doing a CPU upgrade on my 4,1, and I think something has gone wrong on my CPU B's fan connector, or something else. The fan on the heatsink isn't spinning, and the thermal diode isn't recognized.Have I fried it some how? I'm pretty sure its made full connection, as I can't seat it any lower.

Here is a pic of iStat menus
Screen Shot 2016-04-11 at 2.18.18 PM.png


No Booster B detected.

Also, here is a picture of the fan connector
Slack for iOS Upload-1.jpg
 
Last edited:

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
You use de-lidded CPU?
No, I was told the 2mm difference would just require me to be very careful in screwing it down. All CPUs are recognized, and all the RAM is. I did a Geekbench test and the results shatter the old results with the quad core CPUs. The fan connector pic seems like its not all the way down, compared to the other one. I'm tempted to take the pins out and just try that.
 

h9826790

macrumors G5
Apr 3, 2014
12,766
5,577
Hong Kong
That's the problem, you need to mod the connector a bit, otherwise it won't connect. 2mm is a lot for that fan connector.

Update: just saw your updated original post. It seems that you already mod it.
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
That's the problem, you need to mod the connector a bit, otherwise it won't connect. 2mm is a lot for that fan connector.

Update: just saw your updated original post. It seems that you already mod it.
Yeah, the CPU A was easily enough done, but for some reason, this one is a pain. I've hacked a bit at the connector on the board. Really concerned that somehow it has shorted and damaged the tray.

It looks really ghetto, but I did this to make sure it was seating properly. According to the technicians manual, the connector would be the issue. But WHY? I've reseating so many times.
Slack for iOS Upload-2.jpg

[doublepost=1460405785][/doublepost]
That's the problem, you need to mod the connector a bit, otherwise it won't connect. 2mm is a lot for that fan connector.

Update: just saw your updated original post. It seems that you already mod it.
I have it apart again, is there anything I should take pictures of?
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
That's the problem, you need to mod the connector a bit, otherwise it won't connect. 2mm is a lot for that fan connector.

Update: just saw your updated original post. It seems that you already mod it.
Update: the fan kinda 'jerks' and tries to spin. Something power related?
 

666sheep

macrumors 68040
Dec 7, 2009
3,623
211
Poland
Tdiode is one issue (usually reseating and tightening CPU helps), dead fan is another. Check pins in connector.
BTW, you've massacrated it horribly. Cable looks bad as well.
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Tdiode is one issue (usually reseating and tightening CPU helps), dead fan is another. Check pins in connector.
BTW, you've massacrated it horribly. Cable looks bad as well.
Well, yeah, I was doing serious troubleshooting. The pins look good. I've reseated and tightened the CPU multiple times, I guess I could tighten a bit more. Thanks for the input. The cable looks worse in that pic due to flash from my camera and the fact that the whole surface was dusty.

EDIT: tightened until I felt a bit uncomfortable, still the same issue. Could it really be this loose, causing it to not operate without the diode?
 
Last edited:

666sheep

macrumors 68040
Dec 7, 2009
3,623
211
Poland
I've reseated and tightened the CPU multiple times, I guess I could tighten a bit more.
Had this Tdiode issue maybe two or three times, reseating and re-screwing always worked. You need to feel when it's enough. It's hard to desrcibe with words.
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Had this Tdiode issue maybe two or three times, reseating and re-screwing always worked. You need to feel when it's enough. It's hard to desrcibe with words.
I understand. Just nervous since I don't have the washers, don't want to crush a socket. I've taken it out and reinstalled multiple times. I guess if I work up the courage I can go in with some compressed air. I'm a bit wary in doing it again, last time I removed it, I noticed a couple of pins that reflected the light differently, as if they were slightly offset. Was super concerned. No doubt was because of the many times I'd removed and replaced it. Right now, I'm using a fan control application to make the fans quieter, but I am relying on the PCI thermistor to regulate CPU B. Any more insight would be good, but you've posted your solution. I'll update if I get it fixed!
 

666sheep

macrumors 68040
Dec 7, 2009
3,623
211
Poland
Checking pins in CPU socket is good too. Magnifying glass will help. Check contacts on CPU as well. Maybe some dirt/dust or tiny bit of thermal paste got there.
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Checking pins in CPU socket is good too. Magnifying glass will help. Check contacts on CPU as well. Maybe some dirt/dust or tiny bit of thermal paste got there.
I scrubbed the contacts on the CPU (lightly!) with Isopropyl alcohol when I got them. On the CPU B CPU, there was a dark spot on a contact. Could I possibly have received a bad CPU? These are used CPUs, but I was guaranteed them working. I did check the last time I had it off (I had it off over 18 times over the course of two hours) and I didn't see any dust. I'll check for sure when I get it off next.

One of the pins looked like this:
CtYBd.jpg
 

666sheep

macrumors 68040
Dec 7, 2009
3,623
211
Poland
One pin on the left looks burnt/corroded. Group of three pins on the right doesn't look healthy as well (perhaps these three can be cleaned but I can't tell from the pic).
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
One pin on the left looks burnt/corroded. Group of three pins on the right doesn't look healthy as well (perhaps these three can be cleaned but I can't tell from the pic).
Just to be clear, thats not my CPU. Was just an example. The pin on mine looks like the group of three. I tried cleaning it with a toothbrush, but it didn't come off. I'm really starting to think I might have a bad CPU. Would make sense. The fans spin up the same way when there isn't a CPU in the socket. By the tray's logic, no Tdiode means no CPU, therefore, why would we spin the fan on the Booster. I'm getting readings from the thermistor on the heatsink, just not from the Tdiode. If this was overclocked at some point, could that burn out the Tdiode?
 

rawweb

macrumors 6502a
Aug 7, 2015
867
583
Just to be clear, thats not my CPU. Was just an example. The pin on mine looks like the group of three. I tried cleaning it with a toothbrush, but it didn't come off. I'm really starting to think I might have a bad CPU. Would make sense. The fans spin up the same way when there isn't a CPU in the socket. By the tray's logic, no Tdiode means no CPU, therefore, why would we spin the fan on the Booster. I'm getting readings from the thermistor on the heatsink, just not from the Tdiode. If this was overclocked at some point, could that burn out the Tdiode?
Easy to verify, swap CPU A & B, if problem moves with, bad CPU. My opinion? I think you should have bought de-lidded CPU's for a dual 4,1.

If you have anything on the CPU that looks like the pic you posted, I would have sent it back immediately and never put it in my system (if it didn't clean off with careful alcohol treatment).

Either way I'd be horribly concerned with the condition of the connector and wire you pictured. 'Massacrated' was a prefect adjective. Best of luck. :(
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Easy to verify, swap CPU A & B, if problem moves with, bad CPU. My opinion? I think you should have bought de-lidded CPU's for a dual 4,1.

If you have anything on the CPU that looks like the pic you posted, I would have sent it back immediately and never put it in my system (if it didn't clean off with careful alcohol treatment).

Either way I'd be horribly concerned with the condition of the connector and wire you pictured. 'Massacrated' was a prefect adjective. Best of luck. :(
Good idea, I'll test once I get the chance. Just tired of taking it apart. I don't have a lot of money, and I need this computer to last for another 5 years minimum. That was the whole point of this upgrade. I agree, I probably should've sent it back. I'm contacting the eBay seller ASAP. As for the connector, please don't judge. This was a free Mac Pro, I am not the original owner, so I have no idea what horrors it was exposed to. I did cut away the side casing, as it was cracked, and it let me know that the contacts were seated all the way. I can take a photo that shows its not that bad. I've already cleaned it up.
 

rawweb

macrumors 6502a
Aug 7, 2015
867
583
Good idea, I'll test once I get the chance. Just tired of taking it apart. I don't have a lot of money, and I need this computer to last for another 5 years minimum. That was the whole point of this upgrade. I agree, I probably should've sent it back. I'm contacting the eBay seller ASAP. As for the connector, please don't judge. This was a free Mac Pro, I am not the original owner, so I have no idea what horrors it was exposed to. I did cut away the side casing, as it was cracked, and it let me know that the contacts were seated all the way. I can take a photo that shows its not that bad. I've already cleaned it up.
Not trying to offend or pass judgement, but the connector really looks like some kind of creature got in there and chewed the top off, let alone the actual connector on the board. :( It honestly looks like it melted.

You reported this is all on B side. That means if all else fails, you can theoretically still run her with one good working processor in A position, at least I think.
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Not trying to offend or pass judgement, but the connector really looks like some kind of creature got in there and chewed the top off, let alone the actual connector on the board. :(

You reported this is all on B side. That means if all else fails, you can theoretically still run her with one good working processor in A position.
Ah. Sorry, I just get a bit annoyed when people do that. I really don't have a lot of money, and I depend on this machine daily. The B side CPU functions, it just doesn't report temps, thus causing the issues I'm having. Its a rocking fast system now, just the fans are a bit more audible. Thanks for your input! I contacted the seller explaining the trouble I'd been having, hopefully he will take the right step in helping me.
 

rawweb

macrumors 6502a
Aug 7, 2015
867
583
Ah. Sorry, I just get a bit annoyed when people do that. I really don't have a lot of money, and I depend on this machine daily. The B side CPU functions, it just doesn't report temps, thus causing the issues I'm having. Its a rocking fast system now, just the fans are a bit more audible. Thanks for your input! I contacted the seller explaining the trouble I'd been having, hopefully he will take the right step in helping me.
I advise extreme caution in even running that CPU without the fan/heatsink connection working properly. You can do some serious damage and cook things. Are you sure that connector didn't melt from overheating?

My advice: remove the offending CPU until you can verify what's going on. Why risk the entire processor board?
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
I advise extreme caution in even running that CPU without the fan/heatsink connection working properly. You can do some serious damage and cook things. Are you sure that connector didn't melt from overheating?

My advice: remove the offending CPU until you can verify what's going on. Why risk the entire processor board?
I can read temps from the heatsink fine. Even using it for Photoshop, it never got above 60*C. I am running the intake fan much higher. I have multiple alerts setup for this incase it skyrockets, but so far, it hasn't been an issue. I don't even want to touch it unless I have to remove it permanently. I might be stuck with this, depending on what the seller says.
 
  • Like
Reactions: rawweb

rawweb

macrumors 6502a
Aug 7, 2015
867
583
I can read temps from the heatsink fine. Even using it for Photoshop, it never got above 60*C. I am running the intake fan much higher. I have multiple alerts setup for this incase it skyrockets, but so far, it hasn't been an issue. I don't even want to touch it unless I have to remove it permanently. I might be stuck with this, depending on what the seller says.
eBay Money Back Guarantee. I've been burned by it as a seller, but buyers have complete and total control over the situation. http://pages.ebay.com/help/policies/money-back-guarantee.html

All you have to say is it didn't match the listing. If it came with scorch marks that weren't detailed, go ahead and begin the return process. eBay always sides with the buyer.
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
eBay Money Back Guarantee. I've been burned by it as a seller, but buyers have complete and total control over the situation. http://pages.ebay.com/help/policies/money-back-guarantee.html

All you have to say is it didn't match the listing. If it came with scorch marks that weren't detailed, go ahead and begin the return process. eBay always sides with the buyer.
Thanks for the encouragement! I sent the seller a message, and if he doesn't reply, I'll open a case under "didn't match listing"
 

128keaton

macrumors 68020
Original poster
Jan 13, 2013
2,027
401
Problem solved: I swapped the broken 4,1 for a 5,1 at work, for free. Yay levered socket! New CPUs running cool and happeh
 

thornslack

macrumors 6502
Nov 16, 2013
409
159
Too bad you destroyed that 4,1. I highly recommend pindelski's method for changing processors on a 4,1. It's intelligent, methodical, provides easy troubleshooting and requires no additional parts. The guide is down but the archive is available and referenced elsewhere on this forum.