What are those materials and do I need new ones?

[Frandesktop]

I disassembled an R9 290 reference card to replace the thermal paste and then I saw that it has more materials on the VRMs. This card has 2 separate VRM blocks - one long line of VRMs and the second is in the other side and has like 3 VRM chips I think.

 

One looks like this:

And the second:

The little block of VRM seem to have a regular thermal paste (it crumbles in my fingers as dry thermal paste feeling), and the other long-line of VRM has an elastic sort of cover, but it got stuck to the plastic above instead of on the VRMs themselves (I guess that when assembled back, it sits on the VRMs in a good fit because the temps didn't go above 80C)

 

I just wonder if I shoud:

1) Replace this elastic sort of thermal cover (And if so, what material is that? And, do I need to cover the VRM directly, or put it on the plastic as seen in my picture (Under the fan, and then assemble)

2) Apply regular (MX-4) thermal paste to the small block of VRM chips? Or that's not a regular thermal paste?

 

 

Thanks!

[KWelz]

Those are thermal pads.  Looks like the one off the memory is shot.  That one at least needs to be replaced.  All of them look to be pretty rough.   

 

DO NOT use normal thermal paste.  It won't work for this application.  

 

[Frandesktop]

Ok wait I just noticed in my second photo there are 2 types of thermal pads I will edit the photos and show you again:

 

 

And also this:

[KWelz]

I assumed the stuff in the 1st one was a destroyed thermal pad.  They can sometimes crumble like that.  However if there appears to be ones for all the memory modules you should be fine.   As I said, they are in pretty poor shape but if they are not completely dried out they should still work.  

 

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