We appear to be what I would say should/could have been the #1st post, not last or later. Makes more sense and also gives any input some needed
focus.
Buy when you need to.
The 8 core is less than 3 yrs old, and AppleCare should cover most if not all of those issues.
A UPS can really help protect and keep a system up and running I believe very firmly.
Apple Hardware Test isn't as robust as the Service test that a provider has access to.
Every Mac Pro needs to be running SmcFanControl.
There are threads and people have replaced processors with 53xx series in Mac Pro 1,1 or 2,1 model.
Otherwise the whole thing seemed rather academic as to testing, benchmarks, what makes A faster than B and stuff.
How many? Take a look here:
http://store.apple.com/us/browse/home/specialdeals/mac/mac_pro
2008 *Refurbished Mac Pro 8-core 3.2GHz Intel Xeon $3,299.00*
Two 3.2GHz Quad-Core Intel Xeon processors
2GB (2 x 1GB) of 800MHz DDR2 ECC fully buffered DIMM
500GB Serial ATA 3Gb/s 7200-rpm hard drive
Two 16x SuperDrives (DVD±R DL/DVD±RW/CD-RW)
NVIDIA GeForce 8800 GT 512MB (two dual-link DVI ports)
*Refurbished Mac Pro 2.26GHz 8-Core Intel Xeon $2,799.00*
Two 2.26GHz Quad-Core Intel Xeon "Nehalem" processors
6GB (6x1GB) of 1066MHz DDR3 ECC memory
640GB Serial ATA 3Gb/s 7200 rpm
18x SuperDrive (DVD±R DL/DVD±RW/CD-RW)
NVIDIA GeForce GT 120 with 512MB GDDR3 memory
*Refurbished Mac Pro 2.66GHz Quad-Core Intel Xeon $2,149.00*
One 2.66GHz Quad-Core Intel Xeon "Nehalem" processor
3GB (3 x 1GB) of 1066MHz DDR3 ECC memory
640GB Serial ATA 3Gb/s 7200 rpm
18x SuperDrive (DVD±R DL/DVD±RW/CD-RW)
NVIDIA GeForce GT 120 with 512MB GDDR3 memory
Ever hear of the "waiting game?" there is always something better around the next corner. Which is why I was saying, something to get you by for the next 6-9-12 months while new products rollout, mature, graphics cards from ATI & Nvidia have time... and the compulsory EFI/SMC firmware updated and chip revisions during the 4 months plus after anything new is released.
I felt I needed a new system last year and went "Dark Side" of Seven and built a co9uple PCs for firsttime that would have otherwise set me back $$ (and when Gulftown comes out I can just drop it right in). So now I have a test and backup system and a primary workstation.