I'd get the i7 860, in terms of lower power consumption it has a lower TDP of 95W compared to the i7 930's TDP of 130W.
What are you planning to use it for? If what you're going to do isn't intensive, i.e. word processing or watching a movie, a Core i3 530 or a Core i5 750 would be a better choice. If you're going to need all that CPU power, than go for the i7 860. It has a higher turbo boost than the i7 930, and is cheaper too (4/8GB RAM instead of 6/12GB, P55 Motherboards are also cheaper too.)
If you're not going to do anything graphically intensive, then I suggest the Core i3 530 or Core i5 650 - their intergrated graphics are decent enough for most basic applications.
Which cpu would you chose?
i7 860 or i7 930 platform.
I'm not a gamer!
Looking for best managed power consumption for a desk top that only gets used in the evening and never power down.
The more you tell us about what you want to do with your computer, the easier it is to give you help... If you really want low power consumption, get a laptop or netbook. The Core i7-860 and i7-920/930 are some of the most powerful desktop CPUs in the world right now, so buying an i7-920 for evening surfing would be like taking a Ferrari to the corner market to get a ham sandwich.
What do you want to use it for? What is your budget? How long do you want this system to last, realistically? These are some of the major factors that would play into a decision.
The i7-860 uses less power as Lmeow points out, and outperforms the i7-920 in most benchmarks. I put together a comparison review of the two CPUs here. If all you need is a snappy new desktop without special needs (gaming, video editing, etc) and you're concerned with energy, then consider small form-factor PCs like mini-ITX etc.
Thank you both very much. I enjoy reading CPU mag for the past 10 years but not really not a modder / power user. None the less I get excited about all the new components until which time I get sticker shock! I've been waiting for i7 & mother boards to come down in price. I've build one other computer & it's a door stop now! I'm hoping to use the computer for virtualization, using Visual Studio & SQL server. I'm a programmer, which is kind of a stretch lately, but working on windows support/develpment.
My budget is 2k Canadian. I'm will try and use the PSU & Graphic Card & Case from the door stop! I plan on getting another 24" monitor sometime before Christmas.
The I7 930 is cheaper and better as for cost and will also secure the possibility for future upgrades on that socket, but for your needs an I5 750 would be plenty for your needs and will cost alot less roughly a $100 less and will also cost you less for the motherboard and ram too.
Since a monitor has it's own power supply, does getting a second one have anything to do with the PSU ?
No that does not have anything to do with the power supply. It will cause the graphics card to do a little more work and draw a little more juice then it would be with just one but its a matter of a few extra watts nothing crazy.