I'll beat him to it..
Orbs are junk and trying to overclock with one is like playing Russian Roulette. Do someting wrong and BANG. Dead chip. Scrap it and get a real heatsink. For decent price/performance, the Taisol CGK760042 is a great unit and the upcoming Copper Millenium Glaciator is supposed to be pretty incredible when it's finally available. Another option would be the Swiftech MC-370 which is also very impressive - All are discussed extensively in other posts and are around $40.
57 degrees C is quite hot for idle but not enough to panic over. My 1.2@1.33 running at 1.75 volts runs from 38-42 idle and from 48-52 at full load and that's with a very generic CoolerMaster EP5-6i11 and plain grease. The A7V series reports temps higher than other boards (but some say more accurately). If it goes about 65 or so you should probably watch out and clock it back it down untio you can get some better cooling.
Also something to consider is the case cooling - Make sure you've got a couple of fans - At least one intake and one exhaust (which might be covered by your power supply). If your air inside the case is stale, you're going to overheat no matter what you've got for a heatsink.
Best of luck and be careful of your temps! I'd try to run a couple of Sisoft CPU/memory burn-in runs and watch your temps. Make sure they don't get too hot!
- G