Building it myself is not an option because I'm clumsy to the extent that I should get it diagnosed.

I understand, however, if you watch some building videos beforehand and take your time, it's pretty foolproof. Most things are labeled, have a special design so they can only go into a socket in a certain direction, and several plugs only go to one place.

But if you have some legitimate disability, then I understand that this might really be the only option for you. Just don't let fear of clumsiness be the only thing stopping you. I'm sure lots in this community would be willing to give you pointers or a nudge in the right direction.

As for its viability, yes. It should be able to run some older games and less-demanding indie titles. The 5700X has PCIe4 capabilities, so you should be able to get the maximum bang for your buck from the GPU.

Do you happen to know the timings of the RAM? As long as it's C16 @ 3200-3600, you should be golden.

See if you can find someone to build it for you on a work-for-hire type of site. There're tons of people who build their own PCs. If you can find someone who doesn't oversell their skills and is competent, I bet you could have it built for a third of that markup.

Building a desktop in a normal sized case is not some sort of effort in dexterity. Its slow as you want it to be, as careful as you want.

It looks complicated but its basically you get the case on its side, lay the motherboard in there and screw in the like dozen screws all around, get the Power supply in its little spot turned the right way and screw that in. Everything else plugs into the motherboard, and if it needs power you plug a cable into it from the PSU (recommend modular, removable cables).

Usually ram and nvme drives get power from the board directly, stuff like CPU fans and regular fans usually plug into different pins on the motherboard.

You really should be fine with buying parts and just going off of the motherboard manual, it has a diagram showing all the pins and plugs and what goes where.

Just run your build by someone here to make sure you didnt pair something wrong but a lot of it is picking a motherboard and CPU that work together, and then picking GPU, ram, and storage. Cases have size categories so anything in the mid tower size is usually standard, mini is smaller and full is bigger. That mostly depends on how many fans and lights and such you want.

That's way overkill if you just want to run old games and indie games IMO. What's your current specs? Maybe it would be better to just spend a but upgrading your current rig and fixing the cooling issues.