Computer Performance

I have been debating the impact of the larger file size of the D800 file with my current computer.

Model Name: Mac Pro
Model Identifier: MacPro5,1
Processor Name: Quad-Core Intel Xeon
Processor Speed: 2.8 GHz
Number Of Processors: 1
Total Number Of Cores: 4
L2 Cache (per core): 256 KB
L3 Cache: 8 MB
Memory: 16 GB

Given the above specs, would anyone have an idea of how my computer would process an uncompressed NEF file ( around 74MB)? I expect it to be slower, but how much slower when using NX2 or CS5? Your thoughts are appreciated.

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Chris
http://www.flickr.com/photos/crossphotography/