I've always gone (and recommended) Intel chips.
In the old days, it was out of necessity; Intel was always first-to-market on each generation, and really all of the design work was done in their realm. AMD and Cyrix simply copied what Intel had already done. Granted, the AMD and Cyrix chips that came out were faster, and often cheaper, but by the time they had come out, I had already purchased my machine, and been using it for several months. And I always knew that Intel would be around in 6 months, in the event I ran into some obscure problem.
Any more, the reason I go Intel is for compatibility reasons (matching systems for VMware), availability, and cost. AMD isn't the fly-by-night outfit it used to be, but Intel's still a major player across all realms, and any more, interoperability is my domain.
Then again, I'm a person who has some excessive biases when dealing with hardware. For example, one single attempt at using a Diamond video card many, many years ago (somewhere around 1994) made me switch back to ATI, never to abandon the company again for any machine I considered my "main" machine. Oh, I'd get the podunk card for a server that I'd lock away in my server room (at home), but not for a machine I'd sit down at every day.
Until my last machine, I used ONLY SCSI drives. Seagate drives. Before them, a Micropolis here and there. One IBM in the mix. Only Adaptec SCSI controllers, except for that weird 8-bit SCSI controller I got in the early '90's for putting in an old 8088 machine in the days when my home network was Netware Lite, and only because I didn't have an extra machine to dedicate as a Novell 3.11 File Server...in the days before NDS or Active Directory. Heck, I really didn't want Novell; I just couldn't get my hands on the stuff to do a Banyan Vines network.
Only HP LaserJet printers. Only Northgate OmniKey keyboards. Only Kensington ExpertMouse trackballs. Western Digital network cards - Western Digital Elite 16 Combo cards, which then sold to SMC...until 100 megabit networking came around, and I switched to Intel, before finding a lot of good things about LinkSys network cards. Only LinkSys routers around home. NEC, Sony, or ViewSonic for monitors. HP CD-burners. Pioneer DVD burners. Only Creative Labs sound cards. I'd even check a WordPerfect document on my machine to see what kind of floppy drive that was the good one, and what kind was the bad one...I never could remember.
And, invariably, my friends, who go with various other solutions, had more trouble than I did.
On my last machine, due to expense, I decided to branch out a bit...but only a bit. I got a Western Digital IDE/ATA/whatever they want to call it now drive. (I'd only get either WD or Seagate.) I got a LiteOn CD burner. I forget what kind of keyboard I've got, but it's not too annoying. Still have my Adaptec SCSI controller in the machine, to run my scanner. Stayed with ATI for video and Linksys for NIC.
And, I've been MOSTLY solid. I have some strange things going on with video lag on occasion, both in viewing, and in a really weird case, in DVD burning. But that's about it, though.
Part of being picky is by design - saves a lot of trouble remembering tons of different little details. But part of it is based on stability and supportability. The worst nightmare is still hearing, "I'm sorry, but we don't support that platform/configuration." If I *NEED* help, I don't want anyone giving me any reason they're not going to help me.
And, some of that "brand loyalty" extends into the software market as well. I'm probably the only person I know who installs Microsoft Office at home, but never uses Microsoft Word...I use WordPerfect 2000. Why abandon a product that has been exceptionally good to me for one that I think sucks to high heaven?
The downside is that doing computers the way I do them is PRICEY. VERY PRICEY at times. Then again, if you're sitting in a chair, a cheap folding chair DOES WORK and IS CHEAP, but if you're going to sit in it for a while, a GOOD chair is worth the cost.