Given the age of the thing it's more like 256mb ram. Which actually would have been good for the era. 256gb HDDs of the era were a bit more rare. I recall in 2008 a 750gb drive cost me a lot, let a lone 2 of them to run raid0.
Case could make for a sick sleeper build. RGB would light up behind that front plastic alright and you could swap out those trays with some sweet display panels.
Unfortunately probably not; these pre-built cases often are proprietary and won't fit any kind of motherboard you could buy off the shelf. As well as other weirdness like the PSU cage, not being able to remove anything on the front (including the disk drives), etc.
That's nothing an angle grinder, some scrap sheet metal and a tap and die set can't fix. I fit a stupid amount of watercooling into a really shitty case one time doing this.
I run it on my t440p with libreboot!
It takes a while to compile, I didn't update for 3 months, and it took a day 1/2 to finish
minus the compile times, Its rock solid and does everything i want it to do, plus the freedom of gnu/linux and libreboot are a major plus.
I also use Gentoo and I can vouch that it's reliable with the right configuration. I just wish it has a stable version. Never on the Arch Linux level of breaking things tho.