I have heard of that thermal compound but i have not used it yet. At this site its also rated as top pick. So you cant go wrong with it.
www.hardwaresecrets.com/article/Thermal-Compound-Roundup-January-2012/1468/5

Yes I did and temps on my msi lightning 6970 went from 95-104 degrees celsius to acceptable 68-75. You also need to put some moderate pressure on your VGA cooler if the card is positioned in your pc case in standard way so the chip is in better contact with cooling metal. You can also try to tighten screws on the bottom of the card when you put new thermal paste but that needs to be done gently because they tend to break sometimes and then you need to improvise.

I have two favorite ones
1. ANTEC FORMULA 7
2. Zalman ZM-STG2

Hy from Croatia to everyone

I had a problem with low hash rate and i thought it was cgminer. For long time i have searched on all kind of forums and places for help. Yesterday i got to the solution by myself. Everybody told me is the driver is the catalyst is the SDK .. its this its that. You need to push your cards cooler toward the chip. So the thermal paste gets thinner. When i have done that i got my temps where they should be around 70 celsius (they were 102.. and more, that is when i got my cgminer working - low hash on 6970 around 246khs or even less) THAT IS A 30 celsius drop . Todays graphics are big and heavy so if you have them in horizontal or in vertical position it sometimes gets hot specially when mining because chip gets stressed right away thermal grease gets hot and cooler gets a litle fragmet of mm detached from chip and all hell breaks loos errors, pc crashes, cgminer crashes, low hashrate and so on...and so fort. Im considering to take apart every my new build and put my own, quality thermal paste on chips...tightening a screws a bit and all other stuff....

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