Lenovo M Series SFF ThinkCentre M90s Gen 6 SFF Review

A CPU monster trapped in a tiny, graphics-less box with a questionable reliability record. Only buy it if your desk is a closet and your workflow is pure number crunching.

The Lenovo ThinkCentre M90s Gen 6 SFF is a weird one. It's a small-form-factor business PC that's been fed a triple espresso of RAM and a monster CPU, then told to go sit in the corner and think about its life. The one thing to know is this: it's a specialist's tool, not a generalist's dream. It's built for one thing—crushing CPU-heavy workloads in a tiny box—and it does that while completely ignoring everything else, like gaming or, apparently, long-term reliability. That optional NPU is a neat trick for AI tasks, but it feels like putting racing stripes on a forklift.

The performance story is a tale of two halves, and it's exactly what the specs and our database scores predict. That 20-core Intel CPU is a beast, landing in the 86th percentile. For compiling code, running VMs, or number crunching, this thing will fly. But then you look at the integrated graphics, sitting in the 37th percentile, and the abysmal 13.8 gaming score makes perfect sense. This isn't a PC for anything visual. The 64GB of RAM is overkill for most, but if you're the person who needs it, you'll be glad it's there. The surprise is the low reliability percentile (21st). For a business-focused ThinkCentre, that's a red flag we didn't expect to see.

At $1559, the value proposition is shaky unless your needs are hyper-specific. You're paying a lot for that compact chassis and the Lenovo business pedigree. For pure compute power at this price, you could get a much more capable standard tower with a real GPU. This only makes sense if your desk space is at an absolute premium and your workflow is 100% CPU-bound.

Don't even look at the gaming desktops like the HP Omen or Alienware Aurora—they're playing a different sport. A more relevant, if awkward, comparison is against other business SFF PCs or even a Mac Mini. The M90s murders a base Mac Mini in raw CPU and RAM, but you lose the Apple ecosystem, build quality, and resale value. Compared to a Dell OptiPlex in the same form factor, the Lenovo has a more powerful CPU, but you need to ask if you really need that 20-core firepower in a tiny box, especially given the reliability concerns.

If you're looking for a do-it-all desktop, or any kind of gaming or creative PC, this isn't it. Go get a balanced tower like the Lenovo Legion Tower 5i instead. Also, if reliability is your top concern, the low score in our data is a major warning sign to look elsewhere.

We can only recommend the ThinkCentre M90s Gen 6 SFF to a very narrow audience: developers or data scientists who are absolutely maxed out on desk space, need massive CPU and RAM for local workloads, and have zero interest in graphics performance. For everyone else—home office users, general business tasks, or anyone who might ever want to play a game—this is a confusing and overpriced mismatch of components. There are better, more balanced, and likely more reliable options for the money.