Best cooling option for Mac Pro 4.1

[misanthrophy]

Compared to your last results, the new temps look good.

Yea in idle everything is fine.

Now after thinking about, what I saw is, when handbreak starts working, the temperature of CPU A increases much faster before CPU B.

MAYBE the app uses first one CPU fully and then the second one, that would explain why CPU A gets hotter. If thats the case then it is either an issue with Handbreak or expected product behaviour.

Will doublecheck that the next days with running some benchmarks and see if there also CPU A gets hotter. If that happens, that means something is wrong my my heatsink.

As I am now in touch with Noctus regarding new heatsinks and fans for my MacPro that would resolve the issue hopefully!

Overall I am happy so far with the performance and cooling!

 

[handheldgames]

Yea in idle everything is fine.

Now after thinking about, what I saw is, when handbreak starts working, the temperature of CPU A increases much faster before CPU B.

MAYBE the app uses first one CPU fully and then the second one, that would explain why CPU A gets hotter. If thats the case then it is either an issue with Handbreak or expected product behaviour.

Will doublecheck that the next days with running some benchmarks and see if there also CPU A gets hotter. If that happens, that means something is wrong my my heatsink.

As I am now in touch with Noctus regarding new heatsinks and fans for my MacPro that would resolve the issue hopefully!

Overall I am happy so far with the performance and cooling!

CPU A is fed with warm air from cooling: CPUB, CPUB RAM and the Chipset.
The heat is most likely due to the chipset exhaust venting around the base of CPUA.

In the picture below, Cool air enters at the left and exits on the right, The chipset is below the cpu a heatsink. To the left of numbers 2 & 4. CPU A is going to be hotter no matter what you do.

 

[crjackson2134]

CPU A is fed with warm air from cooling: CPUB, CPUB RAM and the Chipset.
The heat is most likely due to the chipset exhaust venting around the base of CPUA.

In the picture below, Cool air enters at the left and exits on the right, The chipset is below the cpu a heatsink. To the left of numbers 2 & 4. CPU A is going to be hotter no matter what you do.

What happened to the pic?

 

[handheldgames]

What happened to the pic?

It should be fixed now.

 

[PowerMac G4 MDD]

If you have not already, do inspect the Northbridge heatsink. Make sure both snap rivets are in place. You may also need to put new thermal paste there, regardless.

 

[misanthrophy]

CPU A is fed with warm air from cooling: CPUB, CPUB RAM and the Chipset.
The heat is most likely due to the chipset exhaust venting around the base of CPUA.

In the picture below, Cool air enters at the left and exits on the right, The chipset is below the cpu a heatsink. To the left of numbers 2 & 4. CPU A is going to be hotter no matter what you do.

But what if I change the direction of both fans? So that Exhaust is the new Intake and Intake is the new exhaust? That would allow to cool down CPU A in first instance.

View attachment 778067

If you have not already, do inspect the Northbridge heatsink. Make sure both snap rivets are in place. You may also need to put new thermal paste there, regardless.

After reading in another thread about the snap rivets, I immediately checked those. Both are intact. But replacing the thermal paste could help.

After a cold boot the IOdiode is at 55C. Now after 15Mins low intense work, just surfing etc. it is already at 63-64C. During high intense workloads (CPU A Heatsink at ~2500-3500RPM) Northbridge stays at ~62. So it remains there.

Other peoples NB temperatures are way higher, so I assume mine is still fine.

Nevertheless when I get my next thermal paste, I will use a new one.
[doublepost=1535399459][/doublepost]I was in touch with Noctua, but due to the special design of the heatsinks/fans they are not able to provide an alternative to the original ones.

They only have a mounting-kit for other heatsinks they offer. For example this one:

https://noctua.at/de/nh-d14-se2011

It looks interesting because both fans would be in one line with the Intake/Exhaust fans, but I am afraid that it wouldn't be enough to cool down the CPU.

What do you think is the maximum time frame I could try it out, until the CPU could get fried?

 

[Matty_TypeR]

Nevertheless when I get my next thermal paste, I will use a new one.

Just remember to clean very very well, liquid metal is not easy to clean off, it also discolours the ICH of the cpu, also check the ICH of the cpu that runs hot, intel have had issues with concave ICH so it touches the outside of the heatsink only or it has a high corner. can be fixed with 1000 grit wet n dry and a very flat surface like a mirror or glass. tape the wet and dry to glass or mirror and damp it, then gently applying light pressure move ICH across the wet and dry, if edges shows copper first the ICH is concave, you can keep going slowly until all the ich is copper, then polish with 2000 grit until mirror like finish. your north bridge temp looks fine, but those plastic clips are prone to breaking. I use a small nut and bolt with nylon washer on back of CPU board and cupped washer on top of spring with positive drive head. much better and will out last the computer.

 

[misanthrophy]

Just remember to clean very very well, liquid metal is not easy to clean off, it also discolours the ICH of the cpu, also check the ICH of the cpu that runs hot, intel have had issues with concave ICH so it touches the outside of the heatsink only or it has a high corner. can be fixed with 1000 grit wet n dry and a very flat surface like a mirror or glass. tape the wet and dry to glass or mirror and damp it, then gently applying light pressure move ICH across the wet and dry, if edges shows copper first the ICH is concave, you can keep going slowly until all the ich is copper, then polish with 2000 grit until mirror like finish. your north bridge temp looks fine, but those plastic clips are prone to breaking. I use a small nut and bolt with nylon washer on back of CPU board and cupped washer on top of spring with positive drive head. much better and will out last the computer.

I already ordered a bunch of new snap rivets just in case they will ever break

Thanks for your input!

 

[PowerMac G4 MDD]

I already ordered a bunch of new snap rivets just in case they will ever break

Thanks for your input!

If you are using the new snap rivets, keep in mind that they're a bit taller than the originals—that you'll have to shave down the nub of the rivet which sits underneath a portion of one of the heatsinks. For this, you can use a sharp blade or a grinding tool. The plastic housing around the spring also needs to be sliced so that it's the same height as the shortened nub.

 

[misanthrophy]

If you are using the new snap rivets, keep in mind that they're a bit taller than the originals—that you'll have to shave down the nub of the rivet which sits underneath a portion of one of the heatsinks. For this, you can use a sharp blade or a grinding tool. The plastic housing around the spring also needs to be sliced so that it's the same height as the shortened nub.

Yea have read that, already saw that they are higher and need to get "shorten", but thx for the reminder

 

[Joey Deacon]

This is a first post - I"m not a wrinkly old man, it's a silly FB account - But you will be a lot better off from reading it! It has solved my issues with heating cooling and noise and everything with my Mac Pro 4.1 which I bought as it was produced, and have kept it running because there is no alternative (Unless you pay $20k or worse here in the UK for new high spec Mac Pro - lol). My fans were noisy whatever I tried, MacFans , opening the case, cleaning everything religiously with comp-air. In the end I bought some Noctua fans confident that with PWM I could control them with Macsfans even if the Pro wouldn't. They don't want to be controlled from the motherboard - Don't bother - Please try this first....(But be good with your hands and a very careful computer tech. It's fiddly and prone to errors, and spares are very hard to get at sensible prices - It can be done though. I promise I now have a better quieter machine than when I bought it, and nothing - except Arctic Silver (and a few screws and O rings required - The exciting part comes at the end...)

I'm no expert, but if you are reading this, you will know how to take the CPU off the tray too, how to remove heatsinks and so on - This isn't for the faint hearted. It is really is a major strip down, clean and reassembly.

Buy some spare black spring clips to hold the Northbridge heatsink down - You will probably break yours too they have been cooking in there for 9+ years and are exceedingly brittle. Do this first. You will be really angry when they break.

Take out your tray and remove the heatsink from the CPU/S (If you have two), remove the main heatsink and give it a really good clean, then take the board off of the tray and pop off the Northbridge heatsink too. Take a deep breath to steady your nerves.

Pop out the two spring clips - Break one and curse hugely (Go to your 30 year old box of spares and find replacements)

Remove the Northbridge heatsink and be amazed that only half of it had a tiny bit of dried up thermal compound on. Clean all the old hard thermal compound off with 100% Alcohol. (NO WATER Not 70% or anything) clean the heatsink too. Put a thin layer of Arctic Silver over the Northbridge - Reassemble carefully after blowing all the dust off.

Clean the CPU and heatsink as you would with any PC cooling mod, then carefully leave to one side after dust blowing, reassembly and so on (If you haven't done this before, I wouldn't bother trying start on this one.

This is far from a starting point for learning computer wizardry - It is downright fiddly, over-engineered, sharp, easy to break, with hard to get spares, it is one long job that feels like bomb disposal.)

I won't break this all down - If you can do it, you will be able to do it already after 10 years - Now remove the fan housing.

[AND NOW BE AWARE OF THIS REALLY AMAZING THING I FOUND!! - My fans had been put in, IN THE FACTORY - Both facing INWARDS, pointing the airflow at each other and cancelling each other out. Effectively cooking the CPU, the Northbridge and creating a horrible air resonance - No wonder that ****** Boost fan ran so loud, and why the IN and OUT fans had to run at differing speeds to achieve any cooling)

The fans are marked with airflow direction FFS! IN at the front OUT at the back - Not both pointing inwards. Jesus, I never expected the thermal compound to be so badly and inaccurately applied to everything and the fans to be installed wrongly in this beautiful machine the day it was built.

Wasn't that all a pain?! (Now take out the five support bolts at the base of the fan housing, loosen the six screws at the back, take off the speaker and two 4 pin fan controllers on the MOBO, release the clips and push the fans inwards to slide out the fan casing - Phew!)

The 120mm Noctua fans are not direct replacements (If you are me - Fit them, run it all up, find it is terrible because nothing works and start again - put your old fans back in again and sigh deeply - Get back to just before you reinstall your fans....)

OK this is important. Chuck out the stupid rubber fan connector mountings. They will be hard and perished and breaking up after all this time. 2 of mine had disintegrated.

Get 8 of those fat little fan screws, and 8 O rings that just fit over them. Clean the fans out thoroughly with air, reassemble everything so that the fans are now held by fan screws with O rings isolating the fan from the caddy. Put everything back together.

Put it all back together.

Relax - It isn't broken (yet)

PART 2: Optional - But I wouldn't go to all the previous trouble and leave this out.

Only do this if you are experienced...

Break down your graphics card completely with the assembly screws if it is the original. Take the whole thing apart and be amazed that the heatsink is totally clogged with fluff, and there is barely any compound on it at all - Clean everything out as best as you can, polish the heatsink where it touches the GPU and apply the usual scraping of Arctic Silver and put a tiny little drop in the centre for good luck - You don't want it spunking out all over everything when you reassemble it so be careful and don't over do it)

Reassemble, reinstall everything.

PART 3: NOT Optional

Reset the SMC

Reset the PRAM

REBOOT!


Now just for the record, and you have to bear in mind that mine was poorly assembled from Day 1 with sketchy thermal treatment, and incorrect fan installation which I would have thought is unusual. But I can't be the only person in the World surely? The person who built mine did build others didn't they?

I forgot to mark the fans up as I removed them from the caddy - I'm glad I did, I thought the fans were just like that. Had I not checked the direction marking on the fan, I would have put it all back together just the same and made the same error - I was assuming Apple had their reasons for building it like that and the in and out non-standard fans just looked like that, and they would not make such a noob error.

So, I had Northbridge that couldn't get below 60 Degrees, and shot to 75+ easily just looking at kittens.

It now runs at 40 odd degrees all day long, even when Handbraking it to death. This was cleaning the **** and fluff out of the very fine fins on the heatsink and rebuilding it all carefully with quality thermal paste.

The CPU is currently running at Just over 30 on the heatsink and diode, with the core under 40 at present!

When all the cores are thrashing with Handbrake, the BOOST fan still kicks off and is noisy, but it is as quiet as a laptop today, and for day to day work silent, and I feel very very pleased with yesterday's work! It is the cool down time which matters to me - I know it will go silent when it has finished the hard work.

I hope this may help someone one day. Even if they find it in years to come.

My MacPro is still fantastic, I love it, I won't change it for an unupgradeable £20k machine fromm Apple - They have lost the plot now. I like messing around with drives, memory, wi-fi and Bluetooth - Beats me why Apple are trying to deter casual users who like experimenting. All that happens is it puts people off buying the machines at all if you can't upgrade them. Mac Pros are not for casual users really, never have been.

If you are on the verge of giving up and moving on to something else because of noise and grief, I would suggest you give this a go first, it is genuinely MUCH better than the day I bought it, and all because I thought the engineers who built it would be like brain surgeons. Not so. It was not well put together. Basically, you could do a lot worse than a complete break down of your 10 year old fluff filled thermal paste requiring Mac, clean and nerdlike careful reassembly. All the slowdowns and stuttering has now gone completely, it seems 'faster' - In reality it's probably just working properly for the first time. I just thought it ran hot like the old G5 used.

Good Luck if you try this - Thank you all for all your information over the years too.

Here's the AFTER screeny of the temps, But all of them are down by 40-50% and everything is set to Auto, with original (correctly installed) fans.

 

[MIKX]

Nice find.

Can you make a SIGNATURE so we can know your cMP setup ?

 

[tommy chen]

i have found a lot of macpro in my life, but i had never experienced that a fan was wrongly installed.

 

[Joey Deacon]

Well it was a surprise, and a Eureka moment. But I have been into computers since the ZX81, BBC Micro and Acorn in the early 1980's and then forever - so I have seen, and fixed, and upgraded a lot of badly built big manufacturer's models with loose bits and faults over the years, including Apple's which haven't always been perfect, since the old pop-up toaster Mac, umpteen Apple laptops, G4s and G5s, most of which which I still have. I didn't really expect to see this scenario though. My temp readings tell the story of what an old MP should run at at idle. (Have you checked all the fans in every single computer you have ever had? What a ball ache if you have, the fan case markings are the least clear I have ever seen - The nose of the fan is a bit of a clue though! :0) Kudos to you for being so thorough though.

The story is what it is. Take it or leave it.

I'll sort out a signature, but it isn't really that interesting. I just thought that one day someone might be interested in this story of how you can never take anything for granted, and perhaps to check that simple things like thermal junctions and airways are in good shape before buying new fans or doing anything rash. Peace.