How long does thermal paste last after tube been opened.

xeph_

Honorable
Jun 12, 2015
102
1
10,685
I have some artic mx4, i used it new in my build, i need to replace on my 4790k, the lid is still on the tube, but some of the paste has got round the side if that helps, its a few weeks old, maybe a month, cant remember, is it allright to use? i ahev some coolermaster ic essential stuff laying around aswell, is it any good if i cant use the arctic mx4?