I have had this tube of MX4 since 2013, it’s served me well, countless rebuilds of my computers, CPUs and GPUs alike, home servers, gaming computers, laptops, games consoles, pi4, I used this on everything. You served me well.
8th June 2013 to 4th November 2023.
I think it doesn’t hurt to try before buying a new tube. If once you apply it you see a drop in temps and fan noise, then it’s obviously still good.