Last time I built a PC was 9 years ago in an higher price range and that PC 9 years ago already had 8GB RAM, upgraded to 16GB 5 years ago
so 16GB RAM seems a bit low nowadays (some games even require at least 16GB (hello borderlands 3, not running with 8GB).
there is a 19'' monitor added - I assume it is already existing (0$) ? I have 3, and never want to go back
I'm not really a fan of fancy RGB stuff in the case itself (since mine is under the desk, and I won't see it anyways)
it just got a single color light which can be turned off. if RGB, I'd use a RGB mouse and RGB keyboard which can be synced and connected to games and stuff
friend of mine got an bright RGB case which he had on his desk, he turned it all off after a month, since it was just distracting
only one SSD with 512GB won't be enough if you plan on keeping a few more games installed though
currently only the games I tend to play regulary take up around 600GB, and I uninstall most games if I am through them
for the price range can't say much - 9 years is quite a time, but I tend to get some high end stuff and use it for a long time, but after a decade more and more games require newer hardware (hello doom, requiring SSE 4.1)
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From @computergenie