The only motherboard I have ever had die here, for any reason, was the VIA Mini-ITX board in our server. Sure enough, the capacitors burst. I replaced all of those (last year), and now it is fine again.

No other motherboards here have required service over the past 20 years. Most of them here are by ASUS and Tyan. Duke, our PVR, has a FoxConn motherboard.

EDIT: actually, one ASUS board I purchased second-hand had to be sent in for warranty service, as the SDRAM sockets were not all functional.

I have replaced the odd lithium-based battery on some motherboards -- those are normally good for up to 10 years or so.

Cheers