Can IC`s which run hot last longer if heatsinks are glued onto IC`s when new ?

I found every hdd ( Seagate, Maxtor ) has at least 1 IC far hotter
than other IC`s. I glue hsinks onto these hot IC`s, to cool them : 1
ata33 Seagate hdd already works noticeably faster, after I glue a
hsink onto its hottest IC. In 12-03 I glued a hsink onto a nVidia
nForce 2 south bridge ( hot ), its IDE controller then worked 5-8
% faster. Now I even fit hdd`s @ an angle ( 45 - 70° ) in casings
so these hsinks can cool faster ; air heated by hsinks can flow
upward faster.
I suspect after IC`s are used for a few years, glueing hsinks will
be too late to extend IC`s' lives ; last week 1 ata100 Maxtor hdd (
bought in 5-02 ) 's IC`s died right after I used Disk Checker to
check all of hdd's 19Gb ( in 1 partition ), despite hsinks glued onto
all the 3 hot IC`s.
Can hot IC`s last longer, from this added cooling ( i.e. hsinks are
fitted ) when IC`s are still new ?


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