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And I'll either be getting this or the 6-core with this in it:

Sorry guys - I've been on vacation since Aug 7th.

So which is more powerful? 4 core i7 with hyperthreading and turboboost or the 4 core Nehalam ? Or are they equivalent? I'd love the 6 core, but I can't justify the cost. I'm pushing it now with $2500.
Also how do the 2 video cards compare ? ATI Radeon HD 5770 1GB vs ATI Radeon HD 5750 1GB GDDR5 SDRAM I assume the 5770 is better? ..but by how much ?

Since I'd upgrade the iMac to the i7- the price difference between that and a MacPro with the Educators discount is very close. I'd get $100 on the iMac and $200 on the MacPro.

Any advise is very much appreciated.

EDIT : Did some quick calcs and there's about $235 difference between the i7 iMac and the MacPro.

MacPro! MacPro! MacPro!

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The video cards are closer in performance than I thought they would be.
The 5770 has a bandwidth of 76.8 compared to 73.6 for the 5750
The 5770 has a fillrate of 13.6 compared to 11.2 for the 5750.
If you are doing Photoshop, the 5750 will work just fine.
If you are doing video editing, you may want to consider the 5770.
If you play some games, then you definitely need to consider the 5770.

The Core i7 is a “desktop” cpu.
The Xeon Nehalem is a “server” cpu.

The Mac Pro uses server cpus which is why it is called a workstation computer.
A server cpu uses advanced memory technology that is not only fast but also reliable.
Server cpus use what is called ECC.
ECC allows data that is being read to be checked for errors and when necessary, be corrected on the fly.
ECC allows a computer to operate even if a memory error occurs.
Server cpus are more reliable than desktop cpus.

Take a look at memory prices.
The Xeon Nehalem processors use more expensive memory.
They use memory with ECC which I talked about above.
ECC=Reliability.

For the vast majority of people though, desktop cpus are plenty reliable.

You ask which cpu has more power.
I don’t know, I’d guess that the Core i7 has more power and can be more easily overclocked.
The Core i7 is the processor of choice for gamers.

If you really want to know the power of the cpus and gpus of the iMac and Mac Pro, keep checking Barefeat’s web site.
They will have benchmarks comparing both systems shortly.
MacWorld will probably have some benchtests also.
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Thanks Clark, you're a real powerhouse of information.

IF it's ~ even, I may want to go Pro because of expandability.... I like the ease of adding drives and new video cards as I grow, plus 4 years from now I may want a better video card. I'm sure the 5750 is plenty now but who knows what the future holds. Plus as new connectivity technology develops I can add faster Firewire and USB cards, or what ever data exchange tech they develop. I was a little disappointed in the iMacs only 1 FW port.

Thanks again - I'll watch for those comparisons.

I remember buying my PowerMac G5 thinking I could upgrade the video card. Silly me....I forget that Apple changes things like that between generations.

Yep...silly Apple... they are always upgrading their systems to the, latest state of the art tech. Dammit.

Many, many thanks to all (esp Clark and John), I've finally made my decision...


and the winna IS . . . .


[drum roll]




the 27" i7 iMac !!

I compared it head to head with the Nehalam 2.8 GHz quad MacPro and each has advantages. But overall I think this iMac gives the most bang for the $. Yeah it's not expandable, but given it's very robust nature - it should easily last me 5+ years - by then I'll be ready for the 72" i20 64-core iMac with 512 Tb of RAM !! .. .. so I can play 3D Tetris !
I plan to head out to the Mall of GA store in a couple of days (Fri or Sat) and pick this baby up... I can't wait for no stinkin' shipping !!
They don't call us Mac Fanatics for no reason !

again thanks to all- you really hepled me immensely.

Getting a wireless KB and mouse so you can back away from it far enough to see the whole screen?

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That will be a very nice machine!
Very powerful with a big, beautiful display.
I've got a friend who desperately wants one but probably can't afford it.
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