So we built one. I'll inherit the hp box I bought her not long after starting this thread. She can't play the games she wants to on it.
Can't seem to get the case fans to come on though. Not sure if they're triggered by temp and the temp just hasn't triggered them yet. There are three in the case and are all wired to this small board on the back side.
There is only one plug left unconnected and I believe it's for some type of led strip add on.