ok..... update.
Got the cap soldered at Sony service station. They did such a good job that you wont even know that it was soldered recently.
Pic here... the one labelled C712 is the one that was soldered.
then installed Silencer but the damn thermal pads are too thick. The core was not making proper contact with heatsink. Idle temps were 80 Dg c. Immediately shut down comp and tried to remove NV Silencer.
but no.... that screw which was loose again got loose(I could not get it soldered at sony service station and had used a drop of Super glue to keep it in place. It again started rotatring with the nut while trying to loosen it. Anyway used a pliers to hold the screw and then loosened the nut properly.
But wait..... more in store. one of the other screws came out completely from the copper base!!!
When you installthe Silencer, supposed to be like this
Tried looseing the nut and the whole damn thing came out.
Dont know what to do for that. I am convinced that it is a manufacturing defect..... And it HAS to happen to me only...... sad....
Anyway, then took the thermal pads from the Silencer and fitted back the stock BFG heatsink. A perfect match!!! Core is now at 54 deg C idle. and 75 deg C load. And it is not with AS5 but some other CoolermasterPremium my dad brought. The reviews of this thermal paste are very discouraging but the performance is as good as AS5.
And I am not able to tighten one side of the Silencer because of that damn screw which keeps rotating with the nut. If I tighten that properly, then I guess the core will make proper contact with the copper base.
Any ideas guys?? For all the problems I have mentioned
but overall, today I will sleep satsified. The card is ok. Ran RTHDRIBL for 2 hrs and no artefacts(didnt expect any

).
Thanks to DJ and Funky.... without their encouraging and hopeful words, I would have been a wreck by now
I also have these thermal pads from Coolermaster. they are thinner than the ones given with the silencer. But they are not enough to fit on 8 Ram chips.
Any ideas?? Or can I try getting hold of more of these coolermaster pads to fit on all the 8 RAM chips?? But in my opinion, if I can get that screw to tighten properly, this wont be necessary.
But before that, how do I put back the screw which came out completely??