Now that is coming in quite a bit under what your budget is, so you could get a better PSU, a nicer case, and/or a better video card. You still don't have all that much money to work with, so you can't go too crazy, but this should give you some ideas to build off of.SNGX1275 said:If you can't build it yourself you are really really limiting what you can get. I really suggest dropping that requirement and doing it yourself, it really is almost impossible to screw up, back in the old days it was slightly more complex, but really it has been pretty easy since I've been doing it, which was 8 years ago.
Here is a build I made a month ago for $314 before shipping. You can't game on it, but for $85 I bet we could find you a video card so you could game.
Western Digital Caviar WD800BB 80GB 7200 RPM IDE Ultra ATA100 Hard Drive - OEM
Intel Core 2 Duo E4500 Allendale 2.2GHz LGA 775 65W Dual-Core Processor Model BX80557E4500 - Retail
MSI P4M900-X LGA 775 VIA P4M900 Micro ATX Intel Motherboard - Retail
FSP Group ATX400-PA ATX12V 400W Power Supply - OEM
Sony NEC Optiarc 20X DVD±R DVD Burner Black IDE Model AD-7190A - OEM
CORSAIR ValueSelect 1GB 240-Pin DDR2 SDRAM DDR2 533 (PC2 4200) Desktop Memory - Retail
Rosewill R624-P BLK Black SGCC Steel ATX Mid Tower Computer Case - Retail
Now, that isn't the nicest case, but when you are putting together something for as cheap as possible, the case is an easy place to cut costs.
I didn't bother to calculate the costs of all that currently, but in late November that came out to about $314. For $88 more (close to your $400 mark) you can get a XFX PVT73GUGF3 GeForce 7600GT 256MB 128-bit GDDR3 PCI Express x16 SLI Supported Video Card - Retail
So... there you go, hopefully you decide you can build it yourself, otherwise, you aren't going to get specs near that good for $400.
Although, having said that, that price doesn't include a KB, monitor, mouse, or operating system. So in that respect, you may be better off getting a lower spec'd machine from Dell or something, where you get everything included.
Edit: Actually, that motherboard won't let you add a PCIe graphics card. So you'll have to find a different motherboard, which will cost more, so you'll have to drop off your video card specs some.... At least what I have listed should give you some ideas though.
Edit2: Actually I found another cheap motherboard that will let you use a PCIe video card: Foxconn 945G7MC-KS2HV LGA 775 Intel 945G Micro ATX Intel Motherboard - Retail. Its probably a better board than that MSI anyway.