I work in a .net body shop, but we have recently taken on some in-house development for a client. As we do most of our work outside the office, the current pcs are underpowered (Pentium D, 2GB RAM, 7200RPM HDD, 17inch monitor).
I am pushing to get us new hardware, but the owner wants to hard facts on why/how it will help.
Does anyone have an personal (or links to sites) benchmarking statistics, particularly around Visual Studio 2008 Web Application projects?
That sounds perfectly... adequate for Visual Studio 2008.
My current system at work isn't much better if any, and it does just fine. I sometimes have 3 or 4 Visual Studio instances and a couple SQL Server Management Studio instances going at once, plus associated text editors and browsers. It's not stellar, it certainly won't win any awards for performance, and there are times now and then when I'm wishing for something faster, but it gets the job done. The biggest bottleneck is usually the disk anyway, and 7200 RPM is still pretty standard.
Where that system will fall down flat is when you start wanting to use Virtual Machines for testing. Then you need something with a real multi-core processor and >4GB RAM to share around.
The only part of your hardware spec that I'd find painful is the single 17 inch monitor. 2GB RAM, 7200 RPM Hard disk and Pentium D, that's perfectly good enough for a majority of Visual Studio development.
I would focus on getting at least two 19 inch monitors. The productivity gains from being able to spread Visual Studio over two monitors, or have Visual Studio on one and documentation on another are great. You will actually work more quickly and have fewer context switches between windows.
Visual Studio has one of the most densely packed user interfaces of any application. (Menus, toolbar icons, code windows, toolboxes, debug windows etc etc). As a result there is very real and valid case for getting large monitors with high resolutions (ie 1600x1200, 1920x1200).
You're going to need two large monitors each to improve productivity: http://www.codinghorror.com/blog/archives/001076.html
To support two monitors, you each might need new video cards. And some systems might need additional upgrades to support that.
Faster cpu and disks reduces the build/test cycle for troubleshooting problems with long-running tasks. That doesn't seem like a lot, but figure what an hour a month of your lost time costs you in a year.