Pada's build is in line with what I'd recommend for a graphic design rig, especially with the Quadro. If it were me...
Intel Core i7 3770 @ R3066
GIGABYTE GA-B75M-D3H @ R822
TEAM Elite Silver DDR3-1600 16GB @ R788
OCZ Agility 4 128GB @ R1181
Western Digital Caviar Red 1TB in RAID mirror @ R2202
Cooler Master GX 400W @ R500
Antec One S3 USB 3.0 @ R508
Windows 7 Professional 64-bit @ R1461
Total: R9422
Now you'll see that there's a lack of a GPU. You and your wife have to decide how you'd like her pictures and colour accuracy to match what you'll see in the final print. A lot of artists and graphic designers don't actually care about this - and I know a few who use regular laptop screens for their work and they don't think it looks crap. I do, because I've seen the difference between a picture edited on a 8-bit screen and a 12-bit professional panel and the
colour depth between the two is noticeable. So there's two options below that you have to choose from and remember, what you see on the screen isn't a reflection of what you'll see on print or in the final project unless you've got the right tools for the job.
Option 1) The Cheaper Route
HP A6R69AA AMD FirePro V3900 1GB DDR3 @ R1277 (
review)
LG IPS235V-BN @ R2009
Option 2) The Professional Route
HP A3J92AA AMD FirePro V4900 @ R2243 (
review)
Asus PA248Q 24" Professional 12-bit monitor @ R6104
The differences between the two might not be so pronounced if you have no experience in monitor panels. The cheaper route uses AMD's FirePro V3900 and a run-of-the-mill 8-bit IPS monitor. It'll do nicely, but the screen's image won't match up even closely to the final printed or real-life product. Colours will look a lot less banded with the monitor and you'll have photos that look a bit more life-like, but its not a professional monitor. The bits refer to the True Colour table the monitor is able to display, with a True Colour 8-bit monitor displaying 16.7 million different colours.
However, most entry-level DSLR cameras shoot at 14-bit True Colour depth - that means you're missing out in a huge amount of information which you should be taking into account. Scanning a photo at high quality? That's 24-bit True Colour depth, way beyond what most monitors will ever manage to render. Printers vary, but most commercial ones start at 10-bit depth if I'm not mistaken.
So the more expensive option uses the FirePro V4900 and ASUS' PA248Q monitor. Its a 12-bit unit so its worth it from an accuracy point of view and has some cool hardware tricks as well, like a powered USB 3.0 hub on the left-hand side. Its also a 16:10 monitor, something necessary for working with pictures if you take them in a 4:3 or 16:10 format. To enable the 12-bit rendering mode, there's
a setting you must turn on in the drivers and in Photoshop. It also helps if you use the Displayport Cable, because most cheap DVI cables only allow for 8-bit video.
Some peeps here have recommended Quadro cards. There are a few CUDA-supported parts of Photoshop and Illustrator, but they're mostly
available through plug-ins that your wife may or may not use. Up until recently there were also specific tools available in Photoshop and Illustrator that were GPU-accelerated only with Quadro cards but with CS6 and all of Adobe's updated suites,
this no longer applies and a varying amount of cards can exploit the new rendering engine by using something called OpenCL.
In a nutshell, you don't need to run a Nvidia card for acceleration for the effects that you apply if you're using the newly-updated versions - you can also use any Radeon card from the HD2000 series up and any Intel Integrated GPU from the HD3000 series onwards. I'd use the FirePro cards anyway since AMD's cards are faster in most benchmarks than competing Quadro variants. If your wife is sticking to older versions of Photoshop and Illustrator, then she'd be better served with a Quadro card if its any version older than the ones bundled in Adobe CS6.
Hope that answers your questions and doesn't confuse!
