Welcome to the path of Gridcoin :)) i promise you, in a few months you will have enough knowledge to discuss with computer science students. Joke aside - For this money, just buy the Gaming PC with best GPU (compare on gpuboss.com). For medical research, you can also just concentrate on a nice CPU. I use cpubenchmark.net for comparing them. But thats just my knowledge - to be honest im not a hardware pro. The art about Gridcoin is that you can just use ANY kind of new PC to help science - if maximizing profits is secondary for you.
If you wanna read a nice article about how people develop a passion for tuning PCs for Gridcoin, read this awesome article by @xaqfields -> https://steemit.com/gridcoin/@xaqfields/i-m-a-boincer-not-a-miner-how-i-built-two-gridcoin-boinc-powerhouses
Followed you to stay tuned on your decision and Gridcoin-journey 😎