Linux

I've got 4 of them, 2 t450s, one that's 8 years old and one that's like 2 or 3 years old, one t560 that's probably about 5 years old and one x260. I'm not a gamer so my spec requirements are quite a bit lower than you if you like to play games with demanding rendering settings.

They all have good CPUs, onboard Intel graphics and 16GB of RAM. All but the oldest one have a 4 core Intel i7 skylake and the older one has an Intel core i5 4 cores, I think ivy bridge. It's the slowest and lowest spec of them all but it still runs like a champ.

I used the older t450 for many years as my main machine, it served me well. Gave the newer one to someone in my family to use, they like it. Tried to migrate to the t560 for my stuff because bigger screen, numpad and all that, and I'm always reminded why I don't like big laptops after I start using one. The hinges are prone to loosening because the display is so heavy, the thing is cumbersome to use when writing code, especially somewhere other than my desk.

I moved over to the tiny almost netbook sized x260 and I'm loving it. The thing has a good CPU and lots of memory, and a secondary onboard battery. I'm a big fan of small machines that pack a punch. The keyboard is kind of small but I find that's actually easier than one that's a little too big, for me personally. It's also just a little spongy and not quite as good quality as the keyboards on the other machines. The display is ~750p LCD and I'm happy with that, I've never been too keen on the constant resolution increases in displays, my ideal is 1080 but I do not care for 4k and have never had a 4k display or any interest in one. I'm happy with the display, the rest of my machines all have a higher resolution display and I still prefer the little guy. I was considering picking up a higher resolution panel for the thing but it's just not that big of a deal to me, the display would cost more than I paid for the machine.