Photoshop CS6 on a dual Xeon E5430... not what I've expected!

[dpcdpc11]

Hey guys... hopefully I'll find some real Gurus here that can help me out with this problem.

I've recently bought a HP xw8600 workstation (2x Xeon E5430, 8GB DDR, Quadro FX 4600, 2x146 SAS HDD in RAID), thinking that this would be a perfect workstation for Photoshop.
I've made a RAID from the two 146GB SAS Hard Drives, and split the memory in 3:
- 87 GB for Windows
- 97 GB for scratch disk
- 71 GB other programs and stuff

All in all the work flow is fluid and you can see the power of this little monster but in Photoshop I was really disappointed! Editing a large file (200cm by 80cm) made PS really laggy which was a surprise since I have 8 Cores to take care of the processing. Taking a closer look at Task Manager, I could clearly see the problem: only one Core was doing the processing and was loading at max every time for example I was quickly zooming in and out or when moving a layer with a bunch of layer style applied. Looking for solutions I've found the so called Core Parking fix which didn't do anything. Going one step forward, I've spent a whole day installing Mac OSX 10.7.4 Lion to see how Photoshop was behaving there. To my surprise in OSX PS used all the cores when working the same large file. So it seems that either Windows 7 limits Photoshop's ability to use all the cores of the CPUs or maybe Photoshop for Windows it self has this limitation.

Later on I've heard a guy saying that he came across some special setting in Windows that would unlock all the Cores in Photoshop and other applications and that he would sell me the solution for 250 Euros. It's hard to believe that he knows something I couldn't find across the whole internet.

So what do you think about all this? Is there a way to make Photoshop CS6 use all the 8 Cores efficiently?

 

[PhilFrisbie]

Only some parts of Photoshop take advantage of multiple cores, and only Adobe can fix that.

Also, you might be better off if your scratch disk was physically a different disk than your boot disk.

 

[dpcdpc11]

Only some parts of Photoshop take advantage of multiple cores, and only Adobe can fix that.

Also, you might be better off if your scratch disk was physically a different disk than your boot disk.

Thanks for the info Phil!
I thought so but it's weird because on Mac OSX Photoshop knows how to handle all the cores and even weirder, on my older machine (intel Q6600) Photoshop CS6 also worked well with all the cores.
Is it something to do with the fact that now I have 2 physical CPUs or the fact that these specific Xeon models are missing some instructions which Photoshop needs?
Really I'm out of guesses here... anyone wanna try his luck at this one?