Well, guys, I gave up on SSDs for my initial build, as the (very new) one I wanted (
http://www.tomshardware.com/reviews/mydigitalssd-bpx-nvme-ssd,4780.html) doesn't seem to have drivers for Win7 or Linux yet, if ever. Other brands are older or out of stock. People on Amazon also had issues getting Win7 to boot from it when they used another SSD's drivers. So I will wait on this, and use a single 1TB hard drive. Anyone know how many disk partitions you can have when using Win7? I would need 3 for Linux Mint, and want the Win7 data separate from the OS, which totals 5 at least.
TDeacon, I'm not an engineer so this is just what I've read and tried to understand. For me it makes sense by thinking about The law of conservation of energy. If you only need 400W, where will the excess go? It doesn't sound to be a viable way to warm up your house, and heat is anyway an enemy to capacitors and other electrical components. A system constantly being 10c warmer than it could be will fail in half the time.
More technically speaking, the excess can/will cause instability in the current, ripple etc.
Skuzzy knows more about electrickery.
Bizman, the 1000W on the PS is just a maximum load rating, which you are not supposed to exceed. What power it actually uses (wall outlet), and delivers (PS output), is a function of the load you attach to it, which varies depending on hardware, which program you are running, and what you are doing at a particular moment in that program. Also, the PPP "400W" figure for my build is low for a worst-case figure, IMHO. For example, compare the ~150W figure they give for the graphics card with worst-case load graphs in various on-line reviews. AND, I still want leeway to put in better graphics cards in 3 years.
Switching power supplies (every computer power supply on the planet) work best when they are under 80 to 85% load. This load is a magic number which keeps the supply electronics working at peak efficiency. The supply runs cooler and produces less noise in the current when running at that load.
It is the very nature of how a switching supply works. Too small of a supply is bad, too big of a supply is bad as both introduce noise and generate more heat.
The closer you can get to an 80 to 85% load, the longer the supply will last and the power quality it will produce will be much better as well. Noise in the power will cause every DC motor (fans, HD's,...) to run hotter and louder. Noise also taxes the power regulators for the CPU.
In short, it is not a good thing to run a switching supply too far outside its 80 to 85% load.
Sounds good in theory, and I am no expert on switching power supplies, but look at the scope traces in the review:
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story4&reid=494 (bottom of page, corresponding the the table just above). Measured at (I assume) the PS outputs, the peak-to-peak AC ripple seems smaller on row 1 (100W) than row 4 (800W). And the power efficiency is almost flat across the range at ~ 90%. So unless I am misunderstanding you, both "efficiency" and "noise" to use your terminology wouldn't seem to be significantly worse at the low end.
And, even if the PS performance weren't this good, I can't see how anyone could keep their PC operating at 80-85% load. I would expect the load to vary hugely between, say, a word processor (low end) and gaming at max settings (high end).
