OT:component level laptop repair places

[eric]

I've seen a few places advertising on eBay as being able to replace 
individual chips on the motherboards of laptops in order to fix no 
video/no sound/no usb/etc problems, rather than replacing the 
motherboard.  It just so happens that I have a Thinkpad R51 with blown 
USB and sound (USB controller chip is recognized, power goes to USB 
ports, but never any data in or out.  Sound controller is never 
recognized, regardless of whether I'm running XP, Vista, Ubuntu, 
Knoppix, or Debian).  Anyone have experience with these places?  Are 
they legit, and actually stand to save me a decent amount over replacing 
the motherboard? 

eric