is too much thermal paste worse than not quite enough? (Not OCing)

[Unclescar]

First time I did a few computer upgrades on my i7 2600k build, I swapped out Intel's stock cooler for a corsair H55. I didn't do it for overclocking, I did it because in just moderate use it was getting very hot, idling in the mid 50s.

At the time of this upgrade, I wasn't quite confident in my ability to properly install a cpu cooler, so I had my buddy who spends a lot of time around computers do it. I don't recall which compound he used, some fancy aftermarket one.
When we initially took the stock cooler off (I didn't install the cooler when building the computer), it was like they hardly used any compound at all. I'm assuming it was preinstalled on the heatsink, like a little sticker, a very thin uneven layer that didn't cover much of the cpu either way.

 

then a few weeks ago, I was prepping the computer for being sold, doing a dust clean out and swapping fans for quieter ones since one had coil wine and the other seemed to be loud and high RPM at all times. I also rearranged some wires and moved the H55 radiator to a place that it fit a bit better. Much more confident in my ability to install a cpu and cooler, I took the cooler off, only to find a thick uneven layer of paste and that some of it had bubbled out the side and dried up on the mobo.

Obviously I cleaned this up with some isoprhoweveritsspelled alcohol and toilet paper, replaced the cooler after using a new tube of ICdiamond thermal compound that I got from microcenter, and things ended up the way I expected them to run, nice and quiet and cool. (even with just an H55, at load it stayed under 60c with a warm ambient temp)

I did Linus's "grain of rice" technique. Guessing it worked since its ran wonderfully and cool since.

But that silly long story aside, I feel like the first time, there wasn't enough compound, and my cpu was running hot, even for a stock cooler which is oviously meh. Then the second time I feel like there was WAY too much, and I had to do it myself to get it right the third time.

So is too much thermal compound just as bad as not quite enough? worse, is it irrelevent and doesn't matter?

[Jobbe03]

It's a fine line (heh double entendres) A bit too much is ok, a bit too little is ok. Too much is just as bad as too little

[Saladin]

So is too much thermal compound just as bad as not quite enough? worse, is it irrelevent and doesn't matter?

Too much thermal compound is bad, probably not as bad as no thermal compound, but pretty bad. Thermal compound doesnt actually transfer heat that well, what it does do is fill in the gap between the internal heat sink of the CPU and the heat pipes/block of the CPU cooler, thus giving it a greater surface area of contact. Therefore you want the absolute minimum needed to do the job, anymore and it becomes much less efficient.

[KeltonDSMer]

Just be very careful with electrically conductive thermal pastes, too much and the excess can short components. Some have silver/aluminum in them for increased thermal transfer but I believe are electrically conductive. Ceramic and carbon based pastes I believe are not conductive, maybe someone can chime in on this. After a minute of searching, it looks like the capacitive properties are also something to consider for the metalic pastes as well.

 

Meh, I realize I don't know much about this so you might want to search on your own. I just wanted to point out that the huge varience in thermal paste composition would make a huge difference whether I would be personally comfortable with the "bit too much paste" approach. I mean, how could silver dust goo possibly be okay near a cpu socket or the components around the GPU on a graphics card?!