>I am guessing that my power supply at 400watts will be sufficient?
If you want to use CUDA via an nVidia card, you may need a bigger power supply... some information on cards in http://www.pacifier.com/~jtsmith/GPU.HTM to show power used
This one - 1 x PCI-e x 16
Couple things ... first check over on the hardware forum for the "tweakers page" ... all sorts of data & comparisons of every bit of hardware that affect video-processing performance. Including wisdom about choosing parts that are equivalent to the capabilities of the rest of the system or "balanced" rather than say stuffing a multi-thousand dollar super-high-end video card in a computer with a slowish CPU, poor bandwidth for i/o capabilities and only 4 gigs of ram. And then coming on here wondering why the playback/rendering didn't start to fly.
We've seen that post numerous times. Almost humorous, you know?
Next, yea, much of any vid-card upgrade these days starts sucking power-supplies pretty good. And John is spot-on to question whether your 400w supply will be adequate. Particularly think about the entire through-put equation: 4-5 internal drives (maybe a pair of discs in a RAID 0 for simple read/write speed as "one" drive of the "four") as a wise choice ... and really, not a particularly expensive way to upgrade your computer's handling of video: splitting different tasks onto different drives. But look at the power you need for this ...
And splitting your disc-intensive tasks between several discs does help through-put, and then putting on that new-ish video card you're looking for will make the most difference you can get for the buck.
John and Neil,
So it sounds like I'll use the
1) PCI-e x16, with a
2) video card that's "balanced" for my system.
I am happy with my hard drives (for now...one (or two!) upgrades at a time!)...so as far as the power supply goes, I'll have to see if that video card puts me over budget on power.
BTW, how does a person add up the power requirements of a given system? Are there some rules of thumb? I could hook up a power meter (Kill-O-Watt) I have to the electric plug on the conputer, does that give a good estimate of what's going on inside?
Use the Power supply calculator http://extreme.outervision.com/index.jsp (the PRO version has more options) to determine your power supply needs
Allow a bit "extra" in the capacity of your power supply
[Moved to Hardware forum.]