dead 9800pro?!

Hello, I think i killed my 9800pro!! I had a crappy o/c of 385/370ish with a silencer and as5. I thought a little help from some ramsinks would help so i bought some, stuck them on with the attached themal pads, installed the card and nothing happens...... only 8 POST beeps which according to the bios means video mem errors. I have now taken off the offending ramsinks. Is this card borked?! Is there anything i can do!?

Many thanks in advance