Thank you

It's probably a little late in the product cycle to buy an i7 9x0 system. Look at the i7 2600K on a Z68 motherboard. You might have a chance of using Ivy Bridge processors down the road. No one knows at this point. Grazie just got a new system that is pretty typical of what can be had these days.

Ivy Bridge ? - yes ! - my own next machine (autumn 2012) is gonna have two Ivy Bridge quad core Xeon equivalents.... at least in my sweet dreams, that is...

I think the 2600k probably is the sweet spot just now. The chip is cheaper, and the motherboards may be cheaper than the X58 motherboards required by a 920, etc., and not too much slower.

However, I just replaced my 940 by a 970 and get results, with air cooling, that are exceptionally close to Kkolbo's 980x on water (see the newrendertest 2010 forum page - link shown above). I paid a bit less than $500, and sold the used 940 for $164 a couple of days ago.

The 970 is about 60% faster than the 940. If you want a chip that is cheaper than the 950, look for a new or used 920, 930, or 940. Whether you would get faster performance with a 940 probably is mostly a matter of luck.

Computers are a time-consuming drag to build. Maybe if you gotta do it, you might want something pretty fast.

If you need a computer now and want excellent speed, the 970 might be the way to go. Another advantage of an X58/1366 motherboard is the additional PCIe lanes. Not only do they enable faster GPUs - or even a pair of GPUs running full speed (which might be a very useful capability with the next version of Vegas), but they also can run many PCI/PCIe devices without slowing down the GPU.

Probably this is not too important (for now) unless some of the on-board peripherals fail, but great if you need good speed for the GPU even though (like me) you may need to replace the failed ethernet chip with a PCI card, and perhaps want to run far too many SATA hard disks (I usually have about a dozen hooked up to my video-editing computer) and must use a PCI card for that, or you want additional USB3 ports (I have a USB3 card to supplement the on-board USB3 ports), or a better sound card, etc. etc. Those additional lanes can come in handy when you want or need several peripheral cards.
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Regarding GPU, I'd recommend nVidia. Seems to be more compatible than alternatives.

I bought a really cheap nVidia on sale at NewEgg for $40 - the GT240 (by ASUS), and it works great even with BCC7 plugins (no crashes). Not the swiftest GPU around, but excellent for my needs (and I do a good bit of work with animation). You'll probably pay more now, but the GT240 still is a pretty good choice.

I also think the biggest bang for the buck right now is the i7-2600 (i7-2600k if you want to OC) on a Z68 mobo. I chose the ASUS P8Z68V-PRO and the 2600k. I am intrigued by the Intel Smart Responce technology and also intel's "turbo" mode which automatically overclocks the processors when running processes that can't use all 8 cores.

It IS time consuming, especially when you are working with some of these "cutting edge" features. There are lots of little "gotchas" that you find out after you did something wrong. I've installed Windows 7 at least 10 times over the last week trying to get everything working.

Vegas 10e loads in less than 2 seconds...... with SSD caching and Smart Response enabled. I finally think that I can put this one in the editing bay and try it out for real. I still have not ventured into Over Clocking yet, I wanted to get the system more or less stable before I start tweaking things.

Given that Vegas doesn't really make much use of video cards anyway, I've elected for now to use the GPU built into the CPU. Again, this board and the i7-2600k will allow overclcking the both the processor and the GPU.

I'll try post some render comparisons between the 2600k and the i7-920 later this week.

I have two systems.

Home - home-built Core i5, Gigabyte motherboard, nVidia 9500 graphics.

Work - HP Z400 6-core Xeon, 12GB RAM, Intel SSD, nVidia GTX460 graphics

Editing AVCHD footage on the timeline is OK on both, but the HP does BEST (Full) quality playback at the full framerate, even with color correction, and the rendering is faster than realtime. The Core i5 render time is about twice as long and it cannot play BEST (Full) on the timeline when affects or transitions are added.

My home system has rare and unpredictable memory errors that cause the system to bluescreen. I'm now on my second HP workstation at work and both have been fast and absolutely rock solid reliable.

A note on graphics: GPU acceleration has been a complete non-starter for me. The HP renders as fast or faster using the 6-core CPU vs. its GPU. My advice: get a less expensive graphics card and spend the $ on your CPU.

A note on SSD drives: the system boots really fast, but other than that save your money.

In terms of productivity, I have two monitors at work (Dell 30" 2560 x 1600 and Dell 24" 1080 x 1200) vs. one at home (HP 23" 1920 x 1080), and that just makes a HUGE difference.

All in all I would estimate my productivity at work as more than double. Part of this is because of the system's raw power and part of it is because editing at work is effortless because I can work as fast as I can think; basically it's like computer isn't even there.

Hey this might be a dumb suggestion, but how long has it been since you too a can of Dust Off from Staples or some other sort of compressed air and sprayed really thoroughlin the fan area?

I mention it because the fans in our various laptions build-up a plethora of icky, furry stuff in just a few weeks. Who knows where it come from . . . all I know is that it causes the computers to run hot and the fan runs non-stop but ineffectively until I dust it away.

You indicated your fan runs constantly so I wanted to mention this. Good luck!