Hey everyone,
So I came across a 2009 Mac Pro a little over a week ago; my brother had hauled it here from college (someone gave it to him for free) so that I could see what was up with it. It had one single symptom of the Northbridge chip reaching past 200F and then causing the Mac to shut off after a few minutes.
And so, I checked online and found out that the plastic rivets holding down these Northbridge chips' heat sinks commonly break/come off and cause the thermal paste underneath to dry out, and - well, you can guess what that does.
Unfortunately, Apple does NOT supply this part anymore, so one has to find other means of seating this heat sink properly. One method is to use thermal adhesive, but I wasn't crazy for that. The other method is to use screws in order to hold the heat sink in place, but that seemed too rough and wouldn't have allowed for much flexibility. I also read of someone doing so and having their chip temperatures only drop a minute amount. Finally, I found out that there's this Akasa heat sink kit that includes two rivets that apparently work......
but I didn't feel like ordering a $10 kit just for two plastic bits.
So, I found this thread: https://forums.macrumors.com/thread...hbridge-rivet-loud-fan.1755982/#post-22305473
This guy claimed that those average, Chinese rivets (found on eBay) worked for him. I was skeptical because they looked much taller than the Apple ones, but I thought I'd give it a try. It was about $2-something for 10 of them and the OP there was able to get them to work.
So, here was my process:
1. Obtain 3mm hex key (long enough for CPU heat sinks), a tube of thermal paste, and plastic rivets from eBay. They are those opaque white ones you see in the other thread.
2. Remove daughterboard from Mac Pro and remove the RAM from their slots.
3. Begin unscrewing the CPU heat sinks on either side. While the NB heat sink only sits partway underneath one of the heat sinks, it's good to get the other one newly thermal-pasted. Unscrew each screw until you hear a noticeable pop/click noise. Note that the screws do NOT physical detach from their screw holes; they are spring-loaded, rather.
4. The processors may become stuck to the heat sinks, so wiggle them off and clean the surfaces of the CPUs and the surfaces of the CPU heat sinks; use rubbing alcohol and a cotton swab or paper towel.
5. Both clips on my Nb heat sink were toast, so they came out without effort. You could pull existing ones out with pliers if they are broken yet still won't fall out, or you can just unscrew the entire daughterboard from her tray and pinch the clips from underneath. I found a cobweb and a dead spider underneath mine, so maybe you ought to do so for the sake of cleaning things out. Make sure you also take the liberty to dust the rest of the machine. I used a 3-gallon air compressor.
6. Clean off the surface of the Nb chip; it's likely that the existing paste will be baked on, so patiently scrape it away.
7. Now, your new rivets come in. These Chinese rivets are a bit tall. You could find smaller ones that happen to fit, but one can't be sure if you happen to have fitting rivets. For these, you're going to have to shave one down to size, as it needs to be concealed underneath one of the CPU heat sinks and not be in the way. Simply take a Dremel or Xacto knife and slice off the top half of the peg. It's unnecessarily tall, so slicing some off gets rid of that and doesn't affect the performance of your rivet. Lastly, there's this plastic, cylinder-like cover over the spring. You want that to be shortened as well, since that will be pushing upwards when you put the rivet in. I practically... circumcised the thing with the Dremel; just cut around the center of that cylinder (being careful not to hit the spring underneath) and you'll have it down to size. Once that excess piece is free, you can cut it in the other direction to free it from the rivet - much like cutting a chain link from handcuffs... not implying anything there.
8. Now, once the Nb chip is cleaned of its old thermal paste, put a smallish blob of new thermal paste in the center of the chip. Position your rivets so that they are simply sitting in their holes on the heat sink. You need to be holding the heat sink with your thumbs over these rivets, so that you can plant the entire thing down and simultaneously push the rivets into their holes on the daughterboard. Make sure you have the shortened rivet on the correct side (I think the CPU A side) and then go for it. Line the rivets up with the daughterboard holes and slowly set the heat sink down. Push both rivets in firmly until you hear/feel a pop. It's okay if one goes in before the other.
9. Now, it's time to thermal paste the cleaned-off CPUs and then place their heat sinks back on! Line up the screw holes and the connector that goes from the CPU heat sinks to the daughterboard. Just slide each heat sink in and press down to get the connector in.
10. Tighten your heat sinks again; do NOT apply too much force once you feel the screw becoming tightened - you can crush your CPUs, etc. Once you feel the screws losing slack, just tighten about a turn or so more. Enacting only a bit of force, you can feel the screw not being able to turn any further. Do not go about this with a ton of force, otherwise, by the time the screw feels like it can't go in any further, you'll likely have already crushed something.
11. Slide it all back in and boot your machine up! First thing: check to make sure all your RAM is recognized. I was able to get my MP to boot, but I realized that only half my RAM was recognized (those in slots 5-7). I tightened my heat sinks a little bit more (as I instructed earlier) and re-booted. It then recognized all 6GB!
12. You're done; make sure you download Hardware Monitor (or something similar) and monitor your Northbridge chip's temps. Note that Northbridge chip AND heat sink will be displayed. Don't confuse them with each other. What are normal temps? Mine goes from 128F from boot and rests around 142F. After doing some web browsing, it seemed to stay there. I believe that's a good temperature; my 2006 Mac Pro's Nb went past 150F. If you are seeing past 170F, you may want to repeat this process and maybe try putting on more thermal paste (or in a better manner) or seeing if the rivets have been seated correctly.
Anyway, there are a lack of guides on this, so that one thread was my savior! I just wanted to give you guys the specifics on what I did. I'm not really sure how that other guy was able to fit his CPU A heat sink over that tall rivet... maybe he just forced the heat sink down and tightened it as it was.
Whelp, I hope you guys found this post useful! I came into this as a n00b (not a n00b in terms of working on computer hardware, but new to the 2009 Mac Pro and its rivet issues) and was able to fix this fantastic machine up. Hopefully it continues to run nicely! Good luck with your machines.
So I came across a 2009 Mac Pro a little over a week ago; my brother had hauled it here from college (someone gave it to him for free) so that I could see what was up with it. It had one single symptom of the Northbridge chip reaching past 200F and then causing the Mac to shut off after a few minutes.
And so, I checked online and found out that the plastic rivets holding down these Northbridge chips' heat sinks commonly break/come off and cause the thermal paste underneath to dry out, and - well, you can guess what that does.
Unfortunately, Apple does NOT supply this part anymore, so one has to find other means of seating this heat sink properly. One method is to use thermal adhesive, but I wasn't crazy for that. The other method is to use screws in order to hold the heat sink in place, but that seemed too rough and wouldn't have allowed for much flexibility. I also read of someone doing so and having their chip temperatures only drop a minute amount. Finally, I found out that there's this Akasa heat sink kit that includes two rivets that apparently work......
but I didn't feel like ordering a $10 kit just for two plastic bits.
So, I found this thread: https://forums.macrumors.com/thread...hbridge-rivet-loud-fan.1755982/#post-22305473
This guy claimed that those average, Chinese rivets (found on eBay) worked for him. I was skeptical because they looked much taller than the Apple ones, but I thought I'd give it a try. It was about $2-something for 10 of them and the OP there was able to get them to work.
So, here was my process:
1. Obtain 3mm hex key (long enough for CPU heat sinks), a tube of thermal paste, and plastic rivets from eBay. They are those opaque white ones you see in the other thread.
2. Remove daughterboard from Mac Pro and remove the RAM from their slots.
3. Begin unscrewing the CPU heat sinks on either side. While the NB heat sink only sits partway underneath one of the heat sinks, it's good to get the other one newly thermal-pasted. Unscrew each screw until you hear a noticeable pop/click noise. Note that the screws do NOT physical detach from their screw holes; they are spring-loaded, rather.
4. The processors may become stuck to the heat sinks, so wiggle them off and clean the surfaces of the CPUs and the surfaces of the CPU heat sinks; use rubbing alcohol and a cotton swab or paper towel.
5. Both clips on my Nb heat sink were toast, so they came out without effort. You could pull existing ones out with pliers if they are broken yet still won't fall out, or you can just unscrew the entire daughterboard from her tray and pinch the clips from underneath. I found a cobweb and a dead spider underneath mine, so maybe you ought to do so for the sake of cleaning things out. Make sure you also take the liberty to dust the rest of the machine. I used a 3-gallon air compressor.
6. Clean off the surface of the Nb chip; it's likely that the existing paste will be baked on, so patiently scrape it away.
7. Now, your new rivets come in. These Chinese rivets are a bit tall. You could find smaller ones that happen to fit, but one can't be sure if you happen to have fitting rivets. For these, you're going to have to shave one down to size, as it needs to be concealed underneath one of the CPU heat sinks and not be in the way. Simply take a Dremel or Xacto knife and slice off the top half of the peg. It's unnecessarily tall, so slicing some off gets rid of that and doesn't affect the performance of your rivet. Lastly, there's this plastic, cylinder-like cover over the spring. You want that to be shortened as well, since that will be pushing upwards when you put the rivet in. I practically... circumcised the thing with the Dremel; just cut around the center of that cylinder (being careful not to hit the spring underneath) and you'll have it down to size. Once that excess piece is free, you can cut it in the other direction to free it from the rivet - much like cutting a chain link from handcuffs... not implying anything there.
8. Now, once the Nb chip is cleaned of its old thermal paste, put a smallish blob of new thermal paste in the center of the chip. Position your rivets so that they are simply sitting in their holes on the heat sink. You need to be holding the heat sink with your thumbs over these rivets, so that you can plant the entire thing down and simultaneously push the rivets into their holes on the daughterboard. Make sure you have the shortened rivet on the correct side (I think the CPU A side) and then go for it. Line the rivets up with the daughterboard holes and slowly set the heat sink down. Push both rivets in firmly until you hear/feel a pop. It's okay if one goes in before the other.
9. Now, it's time to thermal paste the cleaned-off CPUs and then place their heat sinks back on! Line up the screw holes and the connector that goes from the CPU heat sinks to the daughterboard. Just slide each heat sink in and press down to get the connector in.
10. Tighten your heat sinks again; do NOT apply too much force once you feel the screw becoming tightened - you can crush your CPUs, etc. Once you feel the screws losing slack, just tighten about a turn or so more. Enacting only a bit of force, you can feel the screw not being able to turn any further. Do not go about this with a ton of force, otherwise, by the time the screw feels like it can't go in any further, you'll likely have already crushed something.
11. Slide it all back in and boot your machine up! First thing: check to make sure all your RAM is recognized. I was able to get my MP to boot, but I realized that only half my RAM was recognized (those in slots 5-7). I tightened my heat sinks a little bit more (as I instructed earlier) and re-booted. It then recognized all 6GB!
12. You're done; make sure you download Hardware Monitor (or something similar) and monitor your Northbridge chip's temps. Note that Northbridge chip AND heat sink will be displayed. Don't confuse them with each other. What are normal temps? Mine goes from 128F from boot and rests around 142F. After doing some web browsing, it seemed to stay there. I believe that's a good temperature; my 2006 Mac Pro's Nb went past 150F. If you are seeing past 170F, you may want to repeat this process and maybe try putting on more thermal paste (or in a better manner) or seeing if the rivets have been seated correctly.
Anyway, there are a lack of guides on this, so that one thread was my savior! I just wanted to give you guys the specifics on what I did. I'm not really sure how that other guy was able to fit his CPU A heat sink over that tall rivet... maybe he just forced the heat sink down and tightened it as it was.
Whelp, I hope you guys found this post useful! I came into this as a n00b (not a n00b in terms of working on computer hardware, but new to the 2009 Mac Pro and its rivet issues) and was able to fix this fantastic machine up. Hopefully it continues to run nicely! Good luck with your machines.