Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
I have 2 used 3.06 hex core processors I'm in the process of installing in my 09 mac pro. The firmware update is done, the processors are being floated on 5 (each binding post) .5mm metal M4 washers and I have been able to get my mac pro to post with no red lights at all!! (small victory!) For the thermal sensors that the heatsink connects to, I have used a liquid thermal silicone (not conductive) to bridge the gap and it seems to be working... I think my fans aren't spinning.

This is the issue. I turn on the machine with both hex core processors installed and it post's, but after around 30 seconds, a red light on the right of CPU A flashes and the system restarts and won't post... I am thinking I have an issue with the fans not being quite seated correctly and are not spinning on the heat spreaders... There are no RAM lights that show (have done the reseat a few times to get rid of those) but otherwise this is the final issue. I haven't cut the connectors out just yet as I've read that some of the time this isn't needed with washers, any advice would be awesome!
 

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
I reseated and cut the cable connectors, used more thermal silicone and voila, I'm now typing on my dual 6 core... I'm monitoring temps but all ram reads and such... IT turns out it was simply the fans!
[doublepost=1458021981][/doublepost]Spoke too soon, was on it fine for about an hour... Just failed on me and won't post since, seems like an issue with one core as I have verified that all fans are working... DAMN! Everything on my screen went blocky and the system locked up. Thoughts?? Tomorrow I am going to switch back to the 2 quad cores it came with originally and just run those for now.
 
Last edited:

Machines

macrumors 6502
Jan 23, 2015
426
89
Fox River Valley , Illinois
I reseated and cut the cable connectors, used more thermal silicone and voila, I'm now typing on my dual 6 core... I'm monitoring temps but all ram reads and such... IT turns out it was simply the fans!
[doublepost=1458021981][/doublepost]Spoke too soon, was on it fine for about an hour... Just failed on me and won't post since, seems like an issue with one core as I have verified that all fans are working... DAMN! Everything on my screen went blocky and the system locked up. Thoughts?? Tomorrow I am going to switch back to the 2 quad cores it came with originally and just run those for now.

For the DP 2009 Mac Pro upgraded with IHS processors , it is vital that you properly remove the booster fan connector cable from each CPU heatsink for eventual direct re-connection to the CPU Tray . You have to remove a part of the fan connector's keying , while retaining the other keying for proper re-installation of the connector onto the CPU Tray . It's tricky , takes time and hard to explain with words (pictures are mandatory .) You need to reference the appropriate forum thread here at MR .

For the thermal sensors that the heatsink connects to, I have used a liquid thermal silicone (not conductive) to bridge the gap .

You need to apply an additional 2.3 mm layer of high quality thermal gap material onto the bottom of each heatsink . Thermal silicon is not solid enough and likely has too low a thermal conductivity rating .

Thermal gap material looks like this : CSC-Gap-filler.jpg
 
Last edited:

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
For the DP 2009 Mac Pro upgraded with IHS processors , it is vital that you properly remove the booster fan connector cable from each CPU heatsink for eventual direct re-connection to the CPU Tray . You have to remove a part of the fan connector's keying , while retaining the other keying for proper re-installation of the connector onto the CPU Tray . It's tricky , takes time and hard to explain with words (pictures are mandatory .) You need to reference the appropriate forum thread here at MR .



You need to apply an additional 2.3 mm layer of high quality thermal gap material onto the bottom of each heatsink . Thermal silicon is not solid enough and likely has too low a thermal conductivity rating .

Thermal gap material looks like this : View attachment 621218


I now have some on order, it'll be here quickly. I am concerned that something isn't going to work permanently now...
 

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
I've read multiple forums, that's why I finally took the plunge... The heat problem seems to follow one of the two processors when I switch them, but I'll wait until I have proper heat pad in before I try powering it again.
 

leon771

macrumors regular
Sep 17, 2011
213
56
Australia
I did the upgrade and never did anything to mod the fan connectors.
I measured that the gap between having an IHS and not was 2.24mm
With washers spacing at 2.24mm I just my fan plugs fitted back into logic board with no fuss and it's been running well for 3 years now.
I think 2.5mm might be too high.

Did you measure each washer?
I found there was heaps of variability in thickness, so your 0.5mm washers might not actually be that.
 

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
I did the upgrade and never did anything to mod the fan connectors.
I measured that the gap between having an IHS and not was 2.24mm
With washers spacing at 2.24mm I just my fan plugs fitted back into logic board with no fuss and it's been running well for 3 years now.
I think 2.5mm might be too high.

Did you measure each washer?
I found there was heaps of variability in thickness, so your 0.5mm washers might not actually be that.

Thankfully the shop I bought them from measured them for me quick with calipers. They checked out, I've read varying reports on heights. But I don't think that was the issue. The machine won't post of the connections don't match up right? I went the extra mile of cutting them free and manually attaching them before putting the heat sink back on. So, I'm wondering if it's just the sensors. What happened was after an hour of run time and having my about this Mac verify I had all ram running and all 12 cores showing, I suddenly lost my keyboard and mouse, and the screen had visual artifacts all over it (only my main monitor mind you, second seemed ok) distinct slight burn smell and I shut it down instantly. Haven't turned it on again after.
 

Machines

macrumors 6502
Jan 23, 2015
426
89
Fox River Valley , Illinois
I've read multiple forums, that's why I finally took the plunge... The heat problem seems to follow one of the two processors when I switch them, but I'll wait until I have proper heat pad in before I try powering it again.


Do you have a link to the brand of thermal silicon you used on the heatsink .
I did the upgrade and never did anything to mod the fan connectors.
I measured that the gap between having an IHS and not was 2.24mm
With washers spacing at 2.24mm I just my fan plugs fitted back into logic board with no fuss and it's been running well for 3 years now.
I think 2.5mm might be too high.

Did you measure each washer?
I found there was heaps of variability in thickness, so your 0.5mm washers might not actually be that.


Spot on with this concern .

OP , borrow a caliper and measure all those washers . Do not take the advertised thickness at face value , as there is a lot of variation . The precise difference in thickness between a Mac Pro 4,1 (2009) Dual CPU factory IHS-less processor and a X56xx series retail Xeon is 2.3 mm . With your upgrade , the permitted variance is 0.1 mm . That is tiny . So, the permitted range of washer (or total washer set) thickness is 2.2-2.4 mm on each standoff . Too little and you can damage your CPU socket . Too much and the Mac won't start (overtemp alert) or you will have reduced set of processor features . I have built a lot of these Trays .

PS - to leon771 - you were very lucky with the heatsink fan connectors - usually , they have to be removed and directly re-attached to the CPU Tray's connector . If you ship your Mac and it fails on the other end , guess what got loose ? :eek:
 
Last edited:

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
Good advice! I have a set of calipers somewhere so I'll get to measuring at some point soon. I'm waiting on the thermal pads to come in that I ordered and then I'm going to pull it all apart. The part that confuses me is why did it work for just over an hour? And flawlessly!
 

Machines

macrumors 6502
Jan 23, 2015
426
89
Fox River Valley , Illinois
Good advice! I have a set of calipers somewhere so I'll get to measuring at some point soon. I'm waiting on the thermal pads to come in that I ordered and then I'm going to pull it all apart. The part that confuses me is why did it work for just over an hour? And flawlessly!

If this were not a CPU Tray upgrade report, I would suspect dust in the PSU . I have had many clients who bring me unstable Mac Pros , that often function perfectly once all the loose dust inside the System has been removed and all the thermal areas re-pasted with a fresh application of thermal paste (like MX-4) . Either dust blocked something (like the area between the two contact plates of a cMP PSU) or a component overheated . Dust in the PSU will reduce the wattage available to System components . A Mac at idle might operate nicely, but as things heat up or the amount of power drawn by components increases the System can fail .
 

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
It could use more cleaning, I'll give that a shot too! I'm going to take the northbridge heatsink off and rebuild it as I think the plastic caps holding it down are broken too. It can't hurt to get even better thermal paste, I'm using arctic silver 3.
 

Machines

macrumors 6502
Jan 23, 2015
426
89
Fox River Valley , Illinois
It could use more cleaning, I'll give that a shot too! I'm going to take the northbridge heatsink off and rebuild it as I think the plastic caps holding it down are broken too. It can't hurt to get even better thermal paste, I'm using arctic silver 3.

Careful . The two push pins that fasten the Northbridge heatsink in place are Apple proprietary . If they are broken , there are no new replacements available in the computer industry . You'll need to remove the CPU heatsinks , processors , lock in place protective socket caps if you have them , unscrew the PCB from the metal tray in order to expose the lower portion of those black plastic push pins . They are fragile and have by now suffered from thermal fatigue . So be gentle . They can be released by pushing down on them and pinching their ends together with a metal tweezers and then carefully pushing on the end with a soft object (I use the pine handle of one of my bench brushes) . It's under a lot of pressure , so don't be surprised if it shoots out like a bullet and ricochets . Both pins must be undamaged when re-installed or the Northbridge chip will overheat . If your pins are broken, PM me and I'll tell you how to make aftermarket replacements .
 

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
I have FINALLY got the pads... I went about going into the machine tonight to finally change out the thermal for the pads. It was tedious, bent a pin on the processor board by accident but was able to fix it to the point that you can't even see it. After redoing all the thermal, being a bit more liberal with thermal paste, gluing down the fan/thermal sensor wires and then finally putting it all back together and booting, it runs!! Chimed, loaded directly to my user screen, perfect. No red lights on the board, no errors, no burn smell, nothing! So, with my luck running high, I decided to install the new 1333mhz ram I bought not too long ago off of A-Tech ram on eBay. I purchased 4 8gb sticks specifically designed for my mac pro, installed in the correct slots and booted... To a kernel panic. Every time, no matter how little or how much ram, regardless of the stick of ram, panic. I am switching back to what was in the machine prior that worked but now this frustration has me confused... Help?
 

Attachments

  • IMG_0095.jpg
    IMG_0095.jpg
    1.5 MB · Views: 280

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
Decided to reseat my processors one last time... WORKED! The machine is running just fine with the original (and now i find faster) ram installed. Haven't attempted installing the 32gb again but it is running just fine now. I do have one concern, my northbridge temp sensor keeps coming back rather high... around 77C at idle... Is this normal or should I be ripping it apart and redoing the thermal paste on the northbridge?? Any thoughts?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
IMO, not normal, I never re-paste the north bridge, my single processor 4,1 north bridge idle at around 60C (system ambient 34C). I increase the idle fan speed a bit (Booster fan 900RPM, Intake 700RPM, Exhaust 600RPM). And the single processor 4,1 is a little bit cooler, but the difference should not be that much.

There are few possibilities.

1) Heat sink too dusty (both NB and heatsink warm, this is easy to check and fix)
2) thermal paste dried up (Heatsink cool, but NB hot)
3) Rivet broken (this is the worst one. NB temperature increase rapidly when under stress. but should be easy to identify visually)
 

kmangano

macrumors newbie
Original poster
Feb 20, 2016
11
0
I took a closer look, there is a 15C degree difference between the chip temp and the heatsink temp. I remember the pins being both ok when I looked last so I think the paste may have dried out on there. At max cooling, I can get the temps down to much more reasonable levels but there seems to be a difference of a big amount between the heatsink and the chip regardless of cooling level.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.