For a non-gaming machine that will almost exclusively be a photoshop production machine, how much of a performance difference will there be between the E8400, Q6600 and Q9450 CPUs? There is a fairly significant price increase from the E8400 to the Quad processors and I'm wondering if I'll really see that much of a performance difference.

Photoshop can utilize 4 cores, so it would be beneficial to use a quad over a dual in a machine like that. The CPU chart on Tom's shows the E8400 doing quite well, and actually beating the Q6600 on the only test they have, but the 9450 isn't listed. I am guessing that clock speed wins that battle at 3.0 for the E8400 and 2.4 for the Q6600. Both of those chips OC very well, so its easy to get the Q6600 @ 3.0 and the E8400 @ 3.6.

Which version of Photoshop are you going to be using? Are you going to use the new version when it comes out?

We'll be going to CS4 when it comes out, if not right away at least within 3-4 months of its release

Personally, I really have been happy with the Q6600; and it OC well to 3.4-3.6 depending on choice. Even at stock 2.4 or even at 3.0, it performs very well. I would choose a quad going forward for any audio, video or image rendering/applications. I know duals work very well, but the applications you use are far different than web surfing and gaming and clock speeds aren't always going to be the biggest factor in the next couple of years...operating cores WITH speed is where it is scaling towards, along with processing cycles and instruction sets being supported.

I'm out of my depth here, but if you're not an accomplished overclocker and are going to be using the CPUs at stock clock, then the Q9450 would be better for your application.

dirtmountain, I'm not planning on overclocking due to the fact this machine will be running 8-10 hours a day doing lots of batch processing and am afraid of heat issues.

This is the build I'm looking at right now but haven't decided on...I'm contemplating going 4x320G Seagate Drives instead of the 2 500g since the 320g .11 drives perform faster.

Motherboard
ASUS P5K-E/WIFI-AP LGA 775 Intel P35 ATX
CPU
Intel Core 2 Quad Q9450 Yorkfield 2.66GHz LGA 775 95W
CPU Cooler
XIGMATEK HDT-S1283 120mm Rifle CPU Cooler
RAM
CORSAIR XMS2 DHX 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (x2 for 8g total)
GPU
EVGA 256-P2-N751-TR GeForce 8600 GT 256MB 128-bit GDDR3 PCI Express x16
Hard Drives
Seagate Barracuda 7200.11 500GB 7200 RPM SATA 3.0Gb/s (x2 for 1tb total)
Power Supply
CORSAIR CMPSU-520HX 520W ATX12V v2.2 and EPS12V 2.91 Power Supply
Internal Compact Flash Card Reader
Rosewill RCR-103 USB 2.0 Internal Card Reader
DVD Burner
Pioneer 20X DVD±R DVD Burner
Case
NZXT Zero Black/Silver Aluminum ATX Full Tower
Case Fans
Scythe SY1225SL12M 120mm "Slipstream" Case Fans

This is for the 9300, but should give you an idea of how well the 9450 should perform compared to the other CPUs you mentioned.

You'd be OK to run 8-10 hours on the supplied retail cooler. That's what it's designed for. A lot of people OC for 24/7 usage, they just don't push to the limit. I took my 3GHz E8400 up to 3.6GHz, started up 2 copies of prime95, then totally forgot it was running for most of the day (Close the p95 window and it minimises to the tray. I was wondering why things were slow for ages). I didn't even do that properly, just guessed a voltage, cranked up the FSB speed and left it running.

Other than the extreme benchmarking crowd, most OCs have to be stable 24/7. Even gamers won't put up with crashes. To pass as stable an overclock has to run at a guaranteed 100% load on all cores, for at least 8 hours. Your batch processing will never hit that with it pausing to read files in and out.

I hate push pin mounting
http://www.newegg.com/Product/Prod [...] 6835233019

^+1 for the mounting kit.

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