Right screw for additional SSD m.2 drive

[ArnaudJ]

Hello,

I already  searched in former posts but could not found a clear answer.

What screw size do I need to secure an additional SSD M.2 drive in a Z2 G9 tower WS? I found 2 different answers : M3-.50x8 and M2 2 x 3mm. I would appreciate to know the right one !

Txs and br

[SDH]

Neither.

You need one of the special HP M.2 hold-down screw devices that they make two versions of. One has a blue plastic surround as part of the device and the other has black plastic instead. You need the blue type for your workstation. If you bought your Z2 G9 Tower from HP with a NVMe M.2 stick officially in place from the factory then you'll already have a hold down with the blue plastic surround, plus an aluminum HP heatsink on the M.2 stick. Both the blue and black versions have a specially milled brass part with a specially milled Torx head screw that is captured by surface threads in the brass part. The blue plastic version uses a metric M2.0 standard threaded screw. The black plastic version is used in the Z Turbo Drive G1 and G2 versions, the ZTD Quad Pro version, and some other HP computers. The blue plastic version is used in the ZTD Dual Pro v1 and v2 and many other HP computers now. That black one uses a metric M1.6 standard thread screw.  Go to eBay and search as I did in the pic below... these are nicely engineered to work correctly and safeguard your M.2 stick from shorting but you need to get the right version. They also elevate the M.2 stick to provide a gap for airflow across the bottom surface:

HP Blue and Black Versions

Below are 2 pics from a good review of your workstation, and the source link. Note the aluminum narrow HP heatsink and the blue hold down screw on the M.2 SSD. Below those is one picture of your motherboard showing the 3 spots for M.2 sticks. The "SSD1" socket is for your primary boot/applications NVMe-controller M.2 SSD.

Just by eyeballing the motherboard and a few added review pictures it shows that the "SSD2" and "SSD3" positions also use the blue version hold downs. You'd probably want to add on a low profile heatsink as HP does, shown above made of aluminum. I don't know the part number for that official HP one. A HP version I like and have used is all black with part number 919952-001 or -002. I buy the ones that show the official HP part number on the bottom surface. If you get these used off eBay they'll usually be in good shape as long as they have their upper/lower thermal pads. The blue or black HP hold-down devices will work those heatsinks nicely. I've never seen a part number for the HP aluminum colored one shown above. There also are aftermarket low profile M.2 heatsinks. Those 919952-001 or -002 versions might be too wide for the space you have available. Take a close look and note the aluminum one is built quite narrow. There are other after market ones that use flush side screws rather than the wide outrigger spring arms like the black HP heatsink ones.

Motherboard, with the 3 M.2 sites highlighted:

[ArnaudJ]

hello,

Txs for the detailed answer. I have found the right screw kits in eBay, but shipping them to France is rather expensive.

Is there an alternative, using more standard screws ?

In this post https://h30434.www3.hp.com/t5/Desktop-Hardware-and-Upgrade-Questions/nvme-screw-size/td-p/8669685#:~... it is said we have to use M2x3mm screws.

Then there is the standoff to be found, but using a small nylon washer should be ok. It seems that a 2mm thick one should work.

Txs in advance !

[SDH]

NonSequitur777 is only showing you the top third. That M2.0 thread is correct but the length is too short to use by itself. You need a standoff beneath the bottom surface of the M.2 SSD. This will make sense:

NS is only telling you about the top shortie machine screw shown at bottom right. It has a wide head. The top center part of the image shows that shortie screwed into the bottom 2/3 which you would need also. Plus maybe a washer made to be a bit bigger in diameter than the head of the shortie screw. The 2/3 hex shaped part screws into the threads you see on my motherboard pictures. The bulk of that bottom 2/3 is a standoff to elevate the bottom surface about 4mm above the motherboard. It does not matter if the stick slopes up or down just a bit, but you'd never want to just use a metric M2.0 screw to jam the bottom of the M.2 stick against the surface of the motherboard. That would be bad, risky, and potentially ruin your M.2 socket.

Hence, for this important application I advise you to consider spending the few Euros and get the correct blue plastic HP device. However, if you can find exactly the parts I show above that would work also. An aftermarket set for the black plastic equivalent with M1.6 tiny threads surely does not exist. So at least you're starting with M2.0 threads...

[ArnaudJ · Accepted solution]

Hello,

I found the right M2 standoffs + screws to use . They are supposed to be for ASUS ITX mother board, but are perfect  for the Z2 G9 workstation. The standoffs are 2.5mm high, which is perfect. Most kits in the market have too high standoffs, like 6mm or more.

I found them from Amazon. The brand is Xiatiaosann. It is a M.2 SSD kit for Asus, Gibabyte  and MSI mother boards.

See the right ones to use :

IMPORTANT NOTE: my SSD drive is a 3rd-party one, a Samsung 980 Pro. Those screws may not fit for HP SSD Z Turbo drives, but I suppose right screws are included with the HP drives.

ANOTHER NOTE: to screw the standoff on the motherboard can be very delicate using only your hands. It is very small and the hole on the motherboard is not so accessible. A good thing is to use small pliers (typically for electricians) to engage and screw the standoff in the hole.