I use the B3 version of that board, and a bios flash will permit you to run most of the 1155 cpus. Performance is less due to the lack of overclocking with the h61 chipset. My board has a turbo setting, but I didn't notice any performance gain, so I set it back to default settings. You'll need to flash the bios with a sandy bridge cpu just to post with ivy bridge, unless the board just came off the asus line. I recommend a newer H77 or B75 chipset board, which should work without a bios flash.
Thanks for replying
Asus P8B75-M LE < Would this motherboard need flashing?
also if I'm not planning to overclock, will stock cooler for i5 3470 and GTX 650 2GB do? Thanks.