Buying used gaming PC, please rate (help a noob)

[Hiatus]

I am buying a new PC. My coworker who just recently got fired, needs some cash ASAP and basically is trying to flip his gaming PC to everyone who he could still email around the office lol. He apparently bought the PC recently from iBuypower and I'm curious is it worth my wild to select certain parts or buy his whole rig? Any suggestions would really help me out or anything you would swap out or buy separate.

I know building my own would be better, but the guy blew like all his tax return and I have talked him down to $850.
NXZT Vulcan Lan Warrior Case
AMD FX-8350 CPU (8x 4.00GHz/8MB L2 Cache)*I think this is okay.
Motherboard (GIGABYTE GA-78LMT-USB3)*I know nothing about motherboards or hardware really lol.
Memory (8 GB [4 GB X2] DDR3-1600 Memory Module
AMD Radeon HD 7850 - 2GB - Single Card
850 Watt - AZZA Dynamo 850W
Processor Cooling (Liquid CPU Cooling System w/ 92mm Radiator [AMD])
Primary Hard Drive (120 GB ADATA S510 SSD - Single Drive)
Data Hard Drive (500 GB HARD DRIVE -- 16M Cache, 7200 RPM, 6.0Gb/s - Single Drive)
Optical Drive (24X Dual Format/Double Layer DVD±R/±RW + CD-R/RW Drive - Black)
Windows 8 (not sure what version)

[smith303]

That looks like a fair deal for $850.

[Femto]

Being from the U.K PC components are generally more expensive, hence this seems like a cracking deal.
In fact, even for the U.S market you're getting a lot of bang for your buck. The only thing that could be improved is the motherboard, but in a micro ATX form factor you don't have too many options.

The CPU and the GPU are both competent and can run a fair few games on ultra (30 fps), but don't expect to achieve 30 plus frames on demanding games as sadly this will fall short.

For a LAN machine or just a general gaming desktop this should be more than sufficient.

Hope this helps!