Hi, Folks!
Been away from the forums for too long, having fun with WL7! 
Good advice here on buying the biggest, badest, CPU and RAM you can afford for a good MOBO! Also, make sure you’ve got a PSU that’s rated at least 25% higher than the total power consumption you plan to load it up with (HDU’s, MOBO, Video Card, etc.). Just add up each items wattage requirement, and then get a PSU that’ll handle it all plus some reserve to sustain things through power burps, glitches, brown-outs, etc. A good UPS is a wise addition also. I’m partial to APCC’s units; and you can select a UPS that’ll either provide enough power for an orderly shutdown with 15-20 minutes, or keep everything running for a several hours before the batteries give up!
My rather ancient ASUS PC-DL with dual 3.0GHz Xeons and the MOBO’s max 4GB of RAM has held up admirably since I “brewed” it in the early 2,000’s!!! 
However, alas, it’s very much beginning to show it’s age as a 32 bit machine running XP Pro. So, I too am shopping for a new workhorse that will do not only audio, but can handle High Definition video editing also, as I’ve recently been engaged to not only audio record live classical music concerts, but now video them as well! And I suppose while I’m at it I should look into Windows 8, although I’ll likely default it to the Win7 mode, as I still have a fully functional 25-inch CRT monitor and not a “touch screen”! [And sadly, see a lot of these old, likely functional warriors at the town trash station for recycling!] Although, I might be tempted to a couple of widescreens, as they make my “day job” much more productive, and maybe throw in an SSD for boot and applications.
I’d like to get to Blu-Ray disc mastering; got a Pioneer burner for the desktop, but haven’t integrated things to get there until I upgrade.
So, anyone got any suggestions for both audio and video PC’s and video editing S/W? 
Thanks for any insights you folks can provide!