I hate to be the one to give you the bad news but if your title describes your budget then $400 is impossible especially with what you require it to have. The 250gb SSD is about $110, the monitor (just a plain flat panel 23") runs about $140, and the OS, which i'm assuming your going windows, runs you $100-$140 depending on if you go 7 or 8. Just these three things alone get you to $350 at the minimum. You still need a case, Ram, mother board, graphics card, CPU, power supply, and cd or dvd drive. If you don't have a keyboard or mouse then that is more money. I can build a decent PC for around the $600 range but not with the monitor, key board and mouse.