Not to mention the cost of electricity... anyway, when was the last time you saw a 5850 or 5870 on a UK website (new, not overclocked till the original owner smelled smoke and returned it under distance selling regulations ) - let alone for sensible money?

Remember, manufacturers are *still* turning out new designs of cards using the 5830 cores - I spotted a load for sale on videocardshop.co.uk and picked some up, thinking they'd be the same 'Value' 5830 (made by Peak, with two protruding tall heatpipes, every one with snapped fan housing screws, though that didn't stop them working, and all with completely random overclocking potential from extreme to limited).

They weren't - they were new XFX units - a completely new design I hadn't seen before, no complete card shroud, just a spiral-heatpipe fan cooler and a passive heatsink on the VRMs. I haven't tried overclocking these in anger yet, but the one I've got up and running seems OK (around 5˚C hotter than the Peak twin-heatpipe shrouded cards, at 850/300 and around 275 MH/sec).

I presume that all the Cypress cards (5830, 5850, 5870) are effectively the same chip but graded according to defects, right? Or are they specifically designed differently? Seems odd that there's still a supply of *new* Cypress silicon into the market - there's obviously demand because the 5830 is pretty decent in terms of hash per watt in bitcoin mining, but if these new XFX designs aren't just using up surplus production, and AMD are still running Cypress chips on their fabs, then we may be waiting longer for the 78xx cards than expected.

IMO, I'd be happy with identical hashing performance but half the power consumption. In the UK, electricity is the main cost for heavy bitcoin mining...