I don't know anything about the accelerator, but you're saying you disassembled the fan - usually there's a sticker on the underside of many of those types of fans that you can temperarily pull off, and drop a couple of drips of oil into the bearings of the fan. It extends the life (by up to six months, maybe longer) of the fan a bit longer when the fan starts to die. Stick the sticker back on, run the fan upside down for a while to let the oil get around a bit inside, then screw the fan back onto the CPU.
