What should I expect from putting Arctic Cooling MX-4 on my GPU?

[flossbandit]

I've got a mATX board with two 900MHz GTX 560 TIs. Because the board's so small the top GPU gets a lot hotter. When running Furmark the top card touched 96 C while the bottom one sat in the lower 80s and high 70s.

If I put MX-4 on the top card, how much should the temp drop?

 

[flossbandit]

allright i think it's going down today. it's not going to void my warranty or anything is it? it's an EVGA card. this one, specifically:

http://www.newegg.com/Product/Product.aspx?Item=N82E16814130651&Tpk=01G-P3-1567-KR

 

[flossbandit]

Best answer selected by flossbandit.