Lexar NM790 Prices UK: Which Capacity Should You Buy?

The SSD to buy

Our pick is Lexar NM790 2 TB. Our 2 TB choice for a well-equipped Gen4 gaming or everyday PC.

The alternative is Lexar NM790 4 TB. Choose this larger capacity for more installed games, media and projects.

Lexar NM790 2 TB: PCIe 4.0 NVMe, M.2 2280; no heatsink stated. Use the included cooler only where it fits. If no cooler is included, plan suitable motherboard cooling for the installation.

Lexar NM790 4 TB: PCIe 4.0 NVMe, M.2 2280; no heatsink stated. Use the included cooler only where it fits. If no cooler is included, plan suitable motherboard cooling for the installation.

Our choice for capacity before an expensive speed upgrade

The NM790 is our value direction for buyers who need room for Windows, applications and games. A 2 TB version is a sensible starting capacity for a new general-purpose desktop. It leaves substantially more room than 1 TB without immediately paying for a very large drive. The 4 TB version is the better choice for a library that would fill 2 TB quickly.

Choose capacity before a more expensive PCIe generation for this use. A gaming PC normally benefits more from enough space to keep favourite games installed than from replacing a suitable Gen4 drive with a small premium Gen5 model. The NM790 already uses PCIe 4.0 NVMe; it is not a slow SATA drive that must be avoided just because a newer interface exists.

What its design means for normal use

The NM790 uses host memory buffer technology rather than a separate onboard DRAM cache. In a supported PC it can use a small amount of system memory for drive-management information. That is a design choice, not a reason to assume it cannot run Windows or games properly. Our recommendation remains ordinary gaming, applications and capacity-focused storage.

For a workstation that repeatedly writes very large data sets, choose on tested sustained-writing behaviour rather than the highest short sequential speed on a box. A consumer drive's fast write cache is not unlimited. If that is your main workload, a premium alternative can be worth considering for the actual task; it is not required simply to store a game library.

Choose 2 TB or 4 TB directly

Choose 2 TB if your active games, applications and files fit comfortably with space left for updates and growth. Choose 4 TB if you keep many large games installed, work with substantial local media or have only one convenient upgrade slot. Replacing a full 2 TB drive later can be more awkward than buying enough capacity once.

Do not expect the 4 TB version to make every application twice as fast. Its main purchase benefit is twice the nominal storage capacity. A drive advertised as 2 TB also shows less space in an operating system that uses binary units, and formatting and system files take space. Plan around the files you want to keep available rather than a perfectly full headline capacity.

Our alternative and when we would use it

The WD Black SN850X or Samsung 990 PRO is a suitable alternative when its complete price is close, its variant fits better or the required NM790 capacity is unavailable. For a gaming-first purchase, we would not pay a large premium merely for the label on a Gen4 SSD. Buy the suitable capacity at the better total price.

For a new Gen5 workstation that repeatedly moves large files between equally fast storage, choose an appropriate Gen5 model such as the 9100 PRO or SN8100 instead. That is a different need from adding game space. Keep an NM790 that already serves the job well; a new product generation is not a reason to replace functioning storage.

Buy the internal drive your computer accepts

These are M.2 2280 NVMe drives: small internal modules about 80 mm long. Buy one for a computer that accepts that size and type. A 2.5-inch SATA bay or a SATA-only M.2 socket is a different connection. For a machine without a suitable free internal slot, choose an appropriate external SSD or a supported replacement of its existing drive.

For a desktop with an existing SSD heatsink, the fitting bare-drive variant is usually the simple choice. For a laptop, choose the physical version the laptop accepts rather than a bulky desktop heatsink. The right model name, capacity and physical version need to describe the same product. Do not buy an accessory-only heatsink thinking it contains an SSD.

More game space or a replacement system drive?

If the current Windows drive is healthy and there is a suitable free slot, our simple choice is to add storage and keep the original drive. Install large games or active project files on the new SSD. This gives more space without making a Windows migration a compulsory part of the purchase.

If only one slot is available, a larger replacement may be necessary. Allow for a suitable temporary connection or a fresh installation when planning that replacement. Keep the original data until the new setup and independent backup are working. The purpose of buying more capacity is useful room for your files, rather than creating a migration project without need.

A useful capacity example

Fifteen games averaging 100 GB already use about 1.5 TB before Windows, applications and updates. A 2 TB drive can therefore become tight for a buyer who wants all of them available together. That buyer should choose 4 TB if the budget and device support it. Someone keeping only a few active titles may be comfortable with 2 TB.

Use the same reasoning for media. Working video, exported versions and project cache can occupy space together. The biggest file alone does not describe the whole collection. Choose enough room for the files that stay on this SSD, including growth. More expensive peak performance is a poor substitute for capacity that prevents the drive becoming full.

What else belongs in the storage budget

A working SSD and a backup perform different jobs. Keep an independent copy of photographs, projects and other files you cannot replace. Two partitions on one SSD are still one physical device. Buying a premium brand or a longer warranty does not recover the only copy of a lost project.

For an ordinary personal PC, buy this consumer drive for its intended desktop or laptop use. A server requiring documented hardware protection during power loss is a different purchase and can call for enterprise storage. Do not assume a gaming SSD provides that feature. Put the necessary backup or protection into the budget before paying for a speed premium you may not use.