After watching the YouTube video of what happens to TIM when a piece of glass is pressed down the only sure way is to try it and see if it works. If it does, good. If it does not, do it again. I use very thin MX4 which spreads out like crazy with little pressure. Since it's non-conductive, I don't have to worry about it running out and shorting something.
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MSI P55-GD65 with i5-750 @ 4.0Ghz vcore 1.4 Xigmatek Balder HS/2 120mm fans, Antec EW PSU EA750 750W PNY 16Gb DDR3 1333 One Samsung 840 250GB SSD, one 750Gb WD Black, two 1.5Tb LP Seagates Gigabyte GTX 460 1Gb OC to within an inch of it's life Lite-On 24X DVD burner, LG 12X Blu-Ray burner COOLER MASTER Storm Scout Win 7 Pro 64 Lots of fans spinning with little LED lights blinking