I also experimented abit with a Sapphire 5770 Juniper stock (Not vapor-X)
that doesn't use the phoenix cooler, or those open aired ones... Its in between I guess.
A little OC/UC 960/1000 with Afterburner and tuneup utilities brought it up to 210mhash
Hmm, you might get better value from a DDR3 Setup, not that you need that for mining, but most of the time DDR3 is actually cheaper than DDR2 which is costly to manufacture and uses more voltage to run, also you can reuse the motherboard if mining gets phased out.
Case in point... cheapest DDR3 is 1066Mhz at 12.99 with FREE shipping
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007611%20600006050%20600006060&IsNodeId=1&bop=And&Order=PRICE&PageSize=20Cheapest DDR2 400Mhz is 15.99 with 1$ shipping
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007611%20600006042%20600006060&IsNodeId=1&name=1GBHere is a compatible motherboard.
http://www.newegg.com/Product/Product.aspx?Item=N82E16813157176You could spring a bit more for integrated gfx (I suggest an 880G AMD mobo or 785G), which works ok for the main monitor, with the other two cards completely dedicated, that way you can still use the machine while mining. Bandwidth does not matter for mining, so even a 1x slot with an extender would work.
Those 5770s are little dreams.
I have one OC'd to 1030/467 and get around 240MHs with sub 60C temps at stock voltage, they also pull low wattage.