turns out it's a common problem with that nvidia card
the solder dries out / cracks pretty much dead on the expiry of a 3 warranty (funny, that) and the only solution is (seriously) to stick the GPU into an oven at 385F for 8 mins, which melts the solder, thereby reconnecting the circuitry in the chip. Freaky.
http://www.overclockers.com/the-oven...-with-an-oven/
This has a high success rate, but unbeknownst to many, it also poisons your oven with highly toxic fumes!!!
http://www.sentryair.com/solder%20fume.htm Then one has to chuck out the oven,
lol.
the alternative is to use a heat gun, though that has the problem of controlling the temperature. My heat gun churns out 40C, 400C or 600C, so not sure what to do now....
lol (crying inside)