[CentOS] Laptop with CentOS only & support

Looking for my next linux laptop too, I'm loving this thread.

A tangential yet very much related question:

In the past when I've purchased a computer and put linux on it, I always 
had to keep Windows on it (dual-boot) in case there was a probable 
hardware problem and I had to walk through the tech supporter's manual 
with her doing Windows things to make the determination.  So if I get a 
laptop from dell and it has linux only installed on it by them, can I 
still get tech support from dell for their hardware?  Has anyone been 
down this road yet?