How much should I price this computer?

Hope this is the right forum for this, but anyways I'm looking to sell my older computer. I was thinking 600$ for the whole thing, but I want to know how much you guys would price it for.

Here are the specs

CPU: AMD Phenom ii x4 920 @ 2.8ghz
CPU cooler: Silenx Compact Silent CPU cooler 80mm..? (It was cheap, and I had to replace it cause the stock one was messed up, and I didn't want to use the tunic tower extreme that was on it since I may use it for a later build)
Memory: 4gb of crucial memory. DDR2.
GPU: ATI 4870 512mb
PSU: Antec 500watt (Thats all I know, the older PSU blew, so I bought this one from a local store. Its Antec and 500watts)
Motherboard: TA790gx 128M AM2+ biostar
HDD: 1TB seagate barracuda. (Bought it 2 days ago, installed it like a couple hours ago)
Case: CM storm Sniper
Windows 7 ultimate 64 bit.
Older I think 20 inch led monitor 1280x1024
Dell or Microsoft keyboard, Mouse, mouse pad.

Is 600$ too low of a price or too high?