GPU Heatsink Should it be Upgraded (pics inside)

Here is what came on the card. I removed the heatsink and fan today, MAN a dustcloud came out when I cleaned it off. It looked some some crappy white past was used from the factory and it was not evenly spread out. I applied some silver past and put it on evenly. But with such a small heatsink I was wondering if I should look into a better HSF for it. I am running 635mhz memory / 331mhz core for speed right now. I dont have any temp moniters for the GPU so I cant even tell if it is getting too hot. Does anyone know of a software temp moniter for a GF4 MX card. Made by MSI

Dont think they make em, and as long as the heatsink is not hot to the touch, that one should be fine. But if it is hot, i'd look into a crystal orb or something like that.