MP 1,1-5,1 Cooler Northbridge on The Mac Pro 5,1 Dual CPU

[paulcons]

Wow, I got all sorts of nervous when I started looking at my Northbridge (from 1020 to about 2018 I was blissfully ignorant) temps and started using MacsFanControl to tame my lows 80s to mid to high 70s. I did start looking at the concept of trying too cool it further. THEN I started having issues with my tray, many strange things started happening. So I got a cheap (like 35 bucks) single processor tray, BUT it was from a 4,1 (flashed to 5,1) and my machine is a genuine 5,1. At full speeds, all the internal fans can make quite a racket). The guy sent me a replacement and I was taken aback when I opened it... it was as if completely factory fresh, like I had been made within the last year and sealed in plastic. Never seen a cleaner board before! Well, it's been 2 years now and my Northbridge runs... ~50ºC. Yeas I have a curve set to ramp up the fans a bit if it goes too much over 50! I think my oder board ran into the mid 80s because I have pushed the machine and it lived without air conditioning and I live on the top floor so it can bake a bit where the computer sits. Just an anecdotal conclusion!

 

[KingCornWallis]

So I recently completed this mod and am having less than stellar results: TDiode ~ 77C at idle.

It's just M3x14mm screws, following by stock spring, board, and then nylon washer and bolt. Die and heatsink cleaned with alcohol, TG Kryonaut paste, and spring appears almost fully compressed (no wiggle).

So, assuming my CPU fans aren't broken: could being 'too tight' result in higher temps? the alternative is too loose, but I doubt it.

Have not made any adjustment with macsfancontrol/istat yet.

 

[Sean__Wong]

So I recently completed this mod and am having less than stellar results: TDiode ~ 75C at idle.

It's just M3x14mm screws, following by stock spring, board, and then nylon washer and bolt. Die and heatsink cleaned with alcohol, TG Kryonaut paste, and spring appears almost fully compressed (no wiggle).

So, assuming my CPU fans aren't broken: could being 'too tight' result in higher temps? the alternative is too loose, but I doubt it.

Have not made any adjustment with macsfancontrol/istat yet.

Welcome to the rabbit hole.

 

[Sean__Wong]

Here’s what I did 4 years ago

https://forums.macrumors.com/thread...he-mac-pro-5-1-dual-cpu.2173519/post-28510208

 

[KingCornWallis]

Here’s what I did 4 years ago

https://forums.macrumors.com/thread...he-mac-pro-5-1-dual-cpu.2173519/post-28510208

Very interesting. You have a completed prototype or piece for sale?

Also, updated my post. It's consistently 77C with the Booster fans around 10% utilization, Exhaust around 5%, and nothing on the intake. Strangely, under a GeekBench benchmark I didn't see any change in TDiode temps...and barely any increase in fan activity.

What kind of load/stress test could I put this under to see what the T-Diode would peak at using the System Controlled Fan Curve? Just something super CPU-intensive?

 

[AlexMaximus]

Very interesting. You have a completed prototype or piece for sale?

Also, updated my post. It's consistently 77C with the Booster fans around 10% utilization, Exhaust around 5%, and nothing on the intake. Strangely, under a GeekBench benchmark I didn't see any change in TDiode temps...and barely any increase in fan activity.

What kind of load/stress test could I put this under to see what the T-Diode would peak at using the System Controlled Fan Curve? Just something super CPU-intensive?

If you are looking for a professional printed part, I have one left that never made it into my MP5.1.
You can have it for cheap. Just PM me with your address and I will check what the shipping would be.

 

[fatespawn]

It truly is a Rabbit Hole. Don't bother. Unless you're WAY high (90's or something) it's not worth it - even to repaste the heatsink in many cases. Manual fans control only creates more noise. If you've already repasted the Northbridge and your rivets are in good shape, just make sure it's clean of dust. My dual x5690 idles at about 74-77 all day (every day) and it's been there for the last 5 years.

My dual processor 4,1 at idle

If you want a quiet, cool machine, go get a single processor machine. Those fans idle SO much slower and quieter while keeping everything cool with the single bigger (and less total area) heat sink.

Here's my single processor 4,1 at idle

 

[paulcons]

It turned out what I did solved the issue... and in an interesting way. Bought a used CPU tray, it arrived damaged, the vendor sent me out a replacement init. It looked totally unused it was so clean. My NB runs 50-52 ºC. That was 2 years ago, it's still hanging in there.

 

[avro707]

It turned out what I did solved the issue... and in an interesting way. Bought a used CPU tray, it arrived damaged, the vendor sent me out a replacement init. It looked totally unused it was so clean. My NB runs 50-52 ºC. That was 2 years ago, it's still hanging in there.

Dual or single CPU?

50C is around what I expect for single CPU. The dual CPU machines always run hotter.

My old one used to sound like a wounded banshee at times with the fans speeding up when the NB got warm.

What we need is someone to build a heatsink and fan solution that can be easily added to these old machines. My method to have an extra fan was a bit of a hack to hang the fan off the rear CPU heatsink.

 

[paulcons]

Dual or single CPU?

50C is around what I expect for single CPU. The dual CPU machines always run hotter.

My old one used to sound like a wounded banshee at times with the fans speeding up when the NB got warm.

What we need is someone to build a heatsink and fan solution that can be easily added to these old machines. My method to have an extra fan was a bit of a hack to hang the fan off the rear CPU heatsink.

Single. my old tray ran close to 80º C, I could cool it a bit with Mac Fans Control but only to 75-76º.