MP All Models NVMe SSD Heatsink Installation Guide

[MapleGreen]

Hi there
after some searching and reviewing bunch of installation guide I thought it's better to have more discussion about this matter.
as far as I know NVMe SSD's consist of two main sections : Controller and NAND
It has been said that controller is you want to keep cool, so if we get a heatsink we have to make sure that the heatsink goes over the controller but not necessary the NAND, because NAND actually likes to be warmer
it's better for NAND to be warmer while it's beet written to and it's better for it to be cooler when it's just not been used at all, so we actually wanna avoid the heatsink on the NAND for extended writes but you would wanna keep the controller cool.
here's the picture from Sonnet M.2 PCIe:

as you can see they concentrate to the controller to be cooled more

so here the thing:

I have Kingston HyperX PCIe SSD for my Mac Pro 5.1
and Silverstone Heatsink

so based on what we said so far what is the correct way to install the heatsink? because based on the manufacturer manual after installation it looks like the image below (heatsink on both controller and NAND)

 

[tsialex]

You are making some wrong suppositions here:

• First one is obvious, what you are assuming that the heatsinked chip on Sonnet FUS-SSD-4X4-E3 is a SSD controller, but is a PCIe switch.
• Second one is that Sonnet didn't installed a heatsink over the blades, see this diagram from the manual:
  
  
• Third is a more complex one since NAND cells work better with warmer temperature while writing, but if you keep the whole chip warmer, you degrade the other cells that are just storing data and not doing writes. So, with a tightly integrated device PCB like a M.2 blade, with NAND chips, RAM/cache, controller and lots of passives you have to cool everything to the temperature needed for the controller or you damage it with heat conduction.

 

[MapleGreen]

You are making some wrong suppositions here:

• First one is obvious, what you are assuming that the heatsinked chip on Sonnet FUS-SSD-4X4-E3 is a SSD controller, but is a PCIe switch.
• Second one is that Sonnet didn't installed a heatsink over the blades, see this diagram from the manual:
  View attachment 851646
• Third is a more complex one since NAND cells work better with warmer temperature while writing, but if you keep the whole chip warmer, you degrade the other cells that are just storing data and not doing writes. So, with a tightly integrated device PCB like a M.2 blade, with NAND chips, RAM/cache, controller and lots of passives you have to cool everything to the temperature needed for the controller or you damage it with heat conduction.

Thanks so as you said there is no problem if I install the heatsink like the last picture
So what about the back of the m.2 that exposed to PCIe chassis?
Kingston by default has placed a thermal pad on just the controller while Silverstone thermal pad covers the whole thing

 

[tsialex]

Thanks so as you said there is no problem if I install the heatsink like the last picture
So what about the back of the m.2 that exposed to PCIe chassis?
Kingston by default has placed a thermal pad on just the controller while Silverstone thermal pad covers the whole thing

Predator is 2014/2015 era product, with very high power consumption compared with today’s M.2 blades. It wasn’t a M.2 blade made for Macs and don’t have any power management with macOS whatsoever.

I bet that Kingston never intended it to be used with the high burst and concurrent indexing of recent macOS versions that can enable thermal throttle protection of a 970PRO within 5 minutes of power up when not using a heatsink.

Put thermal pads over everything and install the heatsink.

 

[MapleGreen]

Predator is 2014/2015 era product, with very high power consumption compared with today’s M.2 blades. It wasn’t a M.2 blade made for Macs and don’t have any power management with macOS whatsoever.

I bet that Kingston never intended it to be used with the high burst and concurrent indexing of recent macOS versions that can enable thermal throttle protection of a 970PRO within 5 minutes of power up when not using a heatsink.

Put thermal pads over everything and install the heatsink.

Thanks again will do that and post the result, you are very helpful
as the last question should I remove the label cover from the the SSD?

 

[tsialex]

Thanks again will do that and post the result, you are very helpful
as the last question should I remove the label cover from the the SSD?

Some people remove it after the warranty expires, but you will have a big problem if you ever need to sell the blade.

I don't do it at all, most labels are thermally conductive and when I need a bigger blade, I need to sell the previous to help pay for the new one and removing the label will depreciate a lot the resell value.

 

[MapleGreen]

Some people remove it after the warranty expires, but you will have a big problem if you ever need to sell the blade.

I don't do it at all, most labels are thermally conductive and when I need a bigger blade, I need to sell the previous to help pay for the new one and removing the label will depreciate a lot the resell value.

I just installed as you said, iSat shows temperature decrease around 4 to 5 Celsius
I expected 10 degrees difference or more
37C is it any good?

 

[tsialex]

I just installed as you said, iSat shows temperature decrease around 4 to 5 Celsius
I expected 10 degrees difference or more
37C is it any good?

View attachment 852175
View attachment 852176
View attachment 852177

You have to compare when in heavy use for some time, not when idle.

Check the spec sheet for your blade and see what is the operating range.

 

[MapleGreen]

You have to compare when in heavy use for some time, not when idle.

Check the spec sheet for your blade and see what is the operating range.

In heavy use it goes to 42C

 

[Slash-2CPU]

Long as it's under 50°C, you're in very good shape.