They are all the same (basically) whether internal or external. And yes they will get hot. But too hot will damage them.
Don't know what to tell you other than to contact Samsung support.
I recently purchased this external hard drive and its very hot to touch....after its been connected to the tower .... is this normal ??
I purchased it from ebay http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=300194143270&ssPageName=ADME:B:BCA:AU:1123
Not sure what to think, I didn't think external hard drives got so hot.