Various small heatsinks on motherboards

[SteveSmith1980]

I just noticed recently that a small heatsink on my motherboard fell off. I have no idea how long ago this happened. My computer seemed to run just fine without it.

It is left to the processor, and cover like 3 or 4 small chips. Are these small heatsinks very important? I have 2 of them on my motherboard (except the processor heatsink).

I fixed it, but I didn't bother putting new thermal paste on it. There was already a sticky substance underneath so I assume the substance is still working. What are these small heatsinks for?

 

[GhislainG]

Posting a picture would be helpful - you know what it looks like, but we don't. At a minimum provide info about the motherboard.