If you have the original receipt and it's still under warranty, I would try for 20% less than what you originally paid for it. So if it was 600 euros new, then 480 would be a price that it might move quickly on.
Hello, when i buy it i paid for it 1000 euros, but i was nobby and get *** gpu. now i need 600-500 euros to build new high end gaming system. I have now 1000 euros with more 500 i will have 1500 and with it can build gtx 680 and i7 3770k system