What's better onboard raid or add on raid controller?

[netjack]

Quick question:

for stability and heat reasons, what's better? getting one of those KT333 mobo's w/ a built in raid controller card or using one of those promise ultra raid add on cards? I have the promise card and wanted to know if my new mobo should have the raid or skimp out on it. Only thing is my promise card is ata100 but the raid controller on the mobo is ata133.

thanks for the info

 

[Sukhoi]

If you already have a RAID controller you might as well save some money and get a board without one.