OMEN MAX 16: Upgrading the C Drive to 4TB with a Lexar NM990, PTM and TG Putty

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Hi, YuTR0N here. This time, I’m replacing the SSD in my OMEN MAX 16.

In my previous article (Japanese), I added an SK hynix Platinum P41 to the spare SSD slot. This time, I replaced the original system SSD—the C drive—moving from the stock 1TB drive to a 4TB Lexar NM990.

I thought it would just be an SSD swap… but this drive sits underneath the cooling assembly. That meant replacing the thermal materials on the CPU and GPU too, so I’m documenting that part with photos as well.

The new SSD: Lexar NM990 4TB

I chose the Lexar NM990 4TB, an M.2 2280 NVMe SSD with a PCIe 5.0 x4 interface.

Here’s the original drive: a 1TB SK hynix SSD, with “HFS001TFM9X187N” printed on the label.

For the 4TB NM990, Lexar lists read speeds of up to 14,000MB/s and write speeds of up to 11,000MB/s. Those are manufacturer specifications, not my benchmark results, but this is a Gen5 SSD. Capacity also jumps from 1TB to 4TB—four times as much space.

Cloning Windows with SK hynix’s tool

I migrated my Windows environment using SK hynix’s SSD cloning tool. Rather than installing the operating system from scratch, I copied the contents of the original SSD.

For the cloning connection, I used a UGREEN M.2 NVMe SSD enclosure to connect the SSD over USB.

The main SSD sits underneath the cooling assembly

This is where things differ from the previous upgrade.

Adding a drive to the spare slot only involved installing the SSD. To reach the main SSD, however, you have to remove the cooling assembly. HP’s service manual also instructs you to remove the heatsink before removing the main SSD on models equipped with an RTX 5070 Ti, 5080 or 5090.

Here’s the relevant diagram from the manual.

This next diagram shows how to remove the cooling assembly. The point marked ⑥ is the SSD cover’s fastening location. Shut down the laptop, unplug the AC adapter and disconnect the battery after opening the bottom cover, before starting work. It’s also worth checking the manual for the screw removal sequence and the fan cables.

Thermal material everywhere once the cooler is off

Here’s the motherboard with the cooling assembly removed. There’s white thermal material not just on the CPU and GPU, but on the surrounding components as well.

The underside of the cooler also shows where it was making contact with each component.

With this layout, you can’t simply swap the SSD and close everything back up. HP’s procedure calls for cleaning and replacing the thermal material at the specified locations whenever the heatsink is removed. Along with the SSD, you need to prepare the materials for reassembly. Be sure not to touch liquid metal with your bare hands.

For cleaning, I used fogman industrial swabs, Type D, in a pack of 100. After removing the old material, I also checked that no debris or swab fibers remained on the board.

PTM for the CPU and GPU, TG Putty for the surrounding components

I used these two thermal materials.

For the CPU and GPU contact surfaces, I used CSGR PTM7950. For the surrounding components, I used Thermal Grizzly TG Putty Advance 30g.

PTM comes as a sheet, so you need to prepare it to fit the contact surfaces. Don’t forget to remove the protective film. I chose it because, when I asked what to use on Reddit, people strongly recommended it.

TG Putty is a putty-like thermal material that fills the gaps between components and the cooler.

Thermal Grizzly’s product information and precautions

Here’s what it looked like after the swap. At this point, I was pretty much in “just get it done” mode. The original white material felt almost liquid—or at least moist—whereas the Putty felt dry and crumbly. I’m not sure whether that was because this stock had been stored for a long time, or whether it’s simply like that from the start…

I gave up on sourcing HP’s original gallium-containing thermal material because it didn’t seem readily available. I did buy Conductonaut, but I carry this laptop around a lot and got nervous, so I didn’t use it this time.

An SSD swap that also involved the cooling system

Replacing the main SSD turned into more than just installing a 4TB Lexar NM990: it also involved replacing the thermal materials with PTM and TG Putty.

Even on the same OMEN MAX 16, adding a drive to the spare slot and replacing the main SSD involve very different amounts of disassembly. For the main drive, it makes sense to prepare the SSD, the Windows cloning setup and the materials needed to put the cooling assembly back together. I’ve heard that some lower-spec models let you replace the main SSD without removing the heatsink, but on my RTX 5090 model, heatsink removal is part of the job.

After reassembly, check not only that the SSD is detected and Windows boots, but also that the fans work and the CPU and GPU temperatures look right. Since the cooling assembly has been removed, these checks are part of the process. Once you’re done, why not take a break and play a game?

If you’re adding an SSD to the spare slot instead, take a look at my previous SK hynix SSD upgrade article (Japanese).

BitLocker after the swap

After booting, the secondary drive was locked by BitLocker, so I unlocked it. I then temporarily removed encryption from both drives through “Device encryption” and encrypted them again. I’m not sure whether that was the right way to handle it, but so far, everything seems fine in my setup.