[locustella]

I recently put together a system (my first) incorporating:

intel q6600 g0
asus p5k premium
thermalright ultra 120 extreme

I've had it prime stable at 490 x 7 MHz which I'm happy with, really, but I'm a bit obsessive-compulsive about even numbers and decided to see if replacing the TIM on the stock chipset heatsinks (combined with some airflow alterations) would get me to 500 MHz (or 533, that would be good too ...) on the front side bus. Some people seem to be of the opinion that replacing stock TIM is always a good idea on Asus boards.

On the p5k premium the southbridge, northbridge and one set of pwm chips share a heatpipe. There's a separate removable heatsink on another set of pwms. Here's what the northbridge and southbridge looked like when I got the heatpipe off.

northbridge:


northbridge heatsink:


southbridge:
No picture of that before I cleaned it.

southbridge heatsink:


The pwm heatsinks were clean since they had pads (or tape, unsure of the terminology here) that had not melted. This is the one on the heatpipe with a pad that's thicker than the other one:


Question 1) The application of the stock TIM on the northbridge and southbridge does cover the whole contact area, but it looks a bit thick, doesn't it? Do you think I will see some performance gain from replacing this with AS5?

Having already lapped my cpu heatsink I thought I should lap the chipset heatsinks too. This is what they looked like when I finally got the TIM off (I had to use acetone).

northbridge heatsink:


southbridge heatsink:


pwm (the heatpipe one):


Question 2) Do you think the northbridge, southbridge and pwm heatsinks will benefit from lapping?

However, when I started lapping the separate pwm heatsink it turned out to only have a copper coating:


So, as far as I can tell, it's copper plated aluminum. I should have guessed from the weight, of course ... This is also the case for the whole heatpipe section.

Question 3) Should I lap these and wear the copper layer away or are they better left alone? I'm no expert in this area but I wonder what use a thin copper layer is.

I'm also wondering what to do about TIM on the pwm heatsinks. Since they cover 16 separate chips that may or may not be completely even in relation to each other I'm concerned that all may not contact the heatsink if I replace the pads with Arctic silver ceramique (which I've bought for this purpose). Especially for the one that's part of the heatpipe since it doesn't move as freely. However, when I put the whole heatpipe assembly in place "dry", it doesn't wiggle or rock hardly at all.

Question 4) Do you think I should replace the pwm heat pads with Arctic silver ceramique?

I read in this thread about the S775 board Abit IN9 32X-MAX:

"One thing I would mention though is PWM temps. Mine were high and I did add an 80mm fan and I also folded the heat tape over the PWM chips to make it thicker and that knocked a good 20-30c off my PWM chips. I would recommend you do that as soon as you get the mobo since the tape gets a little gooey after awhile, plus on a bare board it only takes like 15 seconds to remove the heat pipe assembly. I also replaced the heat pads on the NB and SB with AS5."

Is folding the heat pads/tape an option? I thought the object of any TIM, compound/pad/tape, was to give the heat a short and easy way to the heatsink?

Another question on the heatsink covering the chips. If you look closely at this picture of the pwm chips covered by the separate heatpipe, you see that the right-most thingie labelled "R68" is on an angle:


This means the pwm chip in the bottom right corner isn't fully covered.

Question 5) Should I use a file to make an indentation in the heatsink to accommodate the out-of-line R68 thingie?

Thanks for any input!