My 2008 Mac Pro, purchased new, was the most expensive home machine I ever bought:
Model Name: Mac Pro
Model Identifier: MacPro3,1
Processor Name: Quad-Core Intel Xeon
Processor Speed: 2.8 GHz
Number of Processors: 2
Total Number of Cores: 8
L2 Cache (per Processor): 12 MB
Memory: 8 GB
Bus Speed: 1.6 GHz
Boot ROM Version: MP31.006C.B05
SMC Version (system): 1.25f4
Hard drive started having issues a year ago, I put a caviar 1TB in it, has hummed along since.
Video card blew chunks last week, replaced it with a NIB Vapor-X HD 5870 (from a PC build that never happened), it boots only to the desktop, where it reads 5000 series chipset.
I'd love to see that EFI64 stuff working, but I think it's a myth (yes, I've thrown down the gauntlet, that's a challenge).
I am too cheap or too stupid to replace this machine, which doesn't feel slow at all. My main use is creating PC board layouts with Eagle CAD, and then generating build packages along with PDFs containing all the screens and manufacturing instructions, and it works just fine for that.
I do wish it would recognize the chipset better, but again I am too cheap or stupid to shell out for a new Apple card that would.
I guess I'll have this machine until it dies, or I do.