I7 920 Power question

At idle, there isn't a whole lot of difference. At full load, it'll be pretty noticeable.

The max it can draw is 360/efficiency, which if the PSU is remotely modern, is around 360/0.85=425 watts or so. If your PSU is inadequate though, it might cause some problems.

360 Watt is way too low for a PC of that specifications. I'd recommend a 650W real power supply, preferably a major brand. You could post full specs here and I'll calculate the minimum you need, or use this:

http://extreme.outervision.com/psucalculatorlite.jsp

Easy to use and fairly precise.

Prolly forgot to use "capacitor aging".....I use 25%. I came up with 332 watts to which I would normally multiple by 1.5 and select something around 500 watts are better.....that's continuous power watts not peak power which many cheapo vendors inappropriately use to rate their units.

Now if this is a "end of the line" PC, meaning, no future upgrades, I'd get something like:

http://www.newegg.com/Product/Prod [...] 6817371020

If I was thinking, yeah I am gonna upgrade this PC 1 or 2 years down the line, I'd look at:

http://www.newegg.com/Product/Prod [...] 6817371017 or an equivalent by Corsair or PCP&C

If I was thinking med level SLI or a dual GPU card, I wouldn't go less than:

http://www.newegg.com/Product/Prod [...] 6817371018 or an equivalent by Corsair or PCP&C

A Corsair 400 or 450 would be perfect for that system. 650 is WAY overkill.

Not at all. You can run a 4850 and an i7-920 just fine on a good 450. Most people overestimate the power requirements of a modern computer.

Oh, and it's true that more is needed if you want a truly high end video setup, but considering that the OP is currently running a 4670, I wouldn't consider truly high end video as a very likely option.

I advise staying under 80% of maximum PSU load at all times. The OP's system uses max. 230W on the 12V rail, so a minimum of 290W capacity on that rail (24A) is recommended, if that 360W PSU has 290W or more on the 12V rail than it will do, but it will fail once the OP gets a bigger graphics card.

I would agree, if he stayed at "stock" speeds. Capacitor aging only takes you to 322 watts. My 500 watt Antec / Corsair recommendation is intended to give the room and stability you'll need if you are going to OC as well as to keep fan noise down. Lately I have been perusing many 850 watt premium reviews and even on the top of the line models, they recommend no more than 600 watt constant draw on an 850 watt PSU not only to maintain clean power and stability but also the fan noise gets annoying under these loads.

It just has to be recognized that the purchase of a 450 watt PSU is a dead end one. That PSU will never be used in an "upgraded" PC. If you want to keep that PSU thru a vid card upgrade (or 2) and a processor upgrade (or 2) then that 450 watt PSU is going to wind up on a shelf in the closet.

A 4670? Definitely, though not at the highest settings. It'll run any game on the market though.