I'd avoid buying something based on name (Alienware) but I genuinely have no idea if Alienware is good or bad. At one point they were considered good but after being purchased by Dell they were considered bad but things don't just change as simple as that so it's all opinion rather than facts but it works both ways, just because a name is popular doesn't mean it is a good choice.

I have always put together my own computers but I know people who have just bought prebuilt systems and they are equally happy. Putting together your own computer isn't that difficult any more, there's far less than could go wrong and in a way it is quite satisfying. I'm not sure if it works out cheaper or not (to assemble your own) as these larger companies do tend to have a lot of buying power but as a potential cost saving it is worth finding out.

I am a reasonable gamer so my choice has always been based on that more than development. Are you more geared towards development? You can probably get away with a slightly cheaper system if that is the case. As a student you might also want to consider a laptop, with the new 10 series from Nvidia you can get some serious gaming power in them now.

should i buy a very exepsnive pc , and just not have to worry about anything for a really long time?

I'd avoid buying a 'very expensive pc' just because the more it cost the less value for money you get. Get something quite top end but not too top end and it can easily last you 3 years. One of the good points of making your own is you can pick expensive parts where it matters and cheap out in other places (although these prebuilt systems do give you a fair few options now).

i'd wait and see. if the school has requirements. you'd at least need that.

beyond that, it depends on what you want to do on your own. figure that out, and the tools required to do it, and the PC required to run it, and go from there.

in the long run for testing. you'll want a PC that matches the target minimum spec for whatever you're releasing next. that way you know what you have to optimize, and what will be fast enough on the minimum spec PC. you can use things like warp to test high end graphics features your card does not support.

i'm about to upgrade myself to what is a "mid-range" game rig for testing: 4 core, 3+ Ghz, 900 series card or equivalent. i'm currently on 2 core 1.3 Ghz, and on-board graphics chip. its ok for placeholder graphics and developing the rest of the game, but its a little behind the power curve for final graphics.

i wouldn't buy more than you need, odds are it will be obsolete in 2-3 years anyway. at the moment there seems to be a new CPU or GPU coming out every six months. but i believe that's almost over with.

to really do it right, start by selecting the processor and vidcard you want. then shop for boxes based on amount and speed of ram from those with the desired processor. odds are the hard drive will be adequate for your needs. if you plan to run some funky vidcard setup, make sure the motherboard supports it in terms of slots etc. power supply power can also be a consideration. some vidcards recommend a lot of power. get your peripherals. get your vidcard, plop it in. install any software, and your done.

As an alternative to Alienware try here: http://www.cyberpowerpc.com

It would be cheapest to build your own but I don't know how comfortable you are with that idea and if you mess up it's a hassle exchanging parts and troubleshooting.

Also will you be playing games as well as making them?

Will you be making 2d or 3d games or both?

Finally is there anything else you want to do with your PC?

I'm going to buck the trend a little and say that you should consider what monitors to buy as a lot of your time is spent looking at the screen. Go for at least one 1440p monitor (the Dell Ultrasharp ones are pretty good) or even better, 2 of them. The extra resolution over 1080p and extra screen will really help your productivity.

From the looks of your first post, buy a PC from a manufacturer (just not Alienware). I've heard good things about https://www.originpc.com/

As a general guideline for the PC itself:

- Get an SSD of some sort for your main drive (512GB would be ideal). The difference between SSD and HDD is almost night and day.

- Minimum i5 CPU

- 32GB of RAM is more then enough. 16GB minimum for most applications to do with games development

- A decent mid range card (if you are doing VR work then you need to look at the minimum needed)

Also don't forget about mice, keyboard and headset as they factor into the cost.