I bought a referb for $90.00 CAD at a comp store and it mines at 200Mh/s OC'ed.
Only good thing is it has only one power connector on it so it works with a smaller PSU.
Thats not a 5870... your thinking a 5770.
and at this point in the mining game i would expect 90 US dollars spent to get 300 mh/s.
naturally MB/ram/cpu/psu/etc is not factored into that.
Sadly not in the great white north. Ironically our CAD is worth more than your USD to boot!
I just found a referb for $300.00 CAD. I'd love to try mining with this puppy but 300 is too steep!