How strong are the retention modules for the cpu heatsink on motherboards?

[nippyjun]

I wonder how strong the heatsink retention units are on today's motherboards.

Some aftermarket heatsinks are much heavier then the stock ones; what are the chances that one of these large/heavy heatsinks could break of the little tab (or tabs) on the heatsink retention module on the motherboard (those little black tabs)?

The AM2 heatsink retention modules only have 2 tabs (one on each side) to hold the heatsink, wasn't that dumb to not have 3 on each side for strength?

 

[Missing Ghost]

the retention modules that use an external plastic frame are much stronger than the ones that holded the heatsink by the socket.