Why is Photoshop CS4 behaving so oddly on my Vista 64bit?

I've been having massive issues with my machine using Adobe Photoshop CS4 since I've had it. My system specs are as so:

- Vista 64-Bit
- 6 GB of ram
- Intel i7 @ 2.67 GHZ / 2.67 GHZ
- GeForce GTX 260

I also want to note I have ZERO issues with any other software, even 3D modeling software (Cinema4D). Working in large 3D files and rendering, etc - everything is fine. So. In Photoshop CS4, the main problem is [B]SEVERE [/B]mouse-interaction lag. When I first launch the application, things are okay for a bit. As soon as I start working for longer than 25 minutes (very average stuff too - maybe 3 documents open, etc) it starts to hit.

The lag seems to [B]only [/B]affect the canvas area. For example, clicking on actual buttons/interface elements has [B]no lag[/B] at all (toolbar, palette windows) and works totally fine. But normal interaction anywhere in the canvas, and it's like there's a major delay before it PROCESSES my mouse input. Let's say I select the Brush tool. I click+hold on the canvas, and NOTHING will happen for about 8-10 seconds. After this delay, finally it will draw something on the screen, and as I continue moving my mouse, it will draw normally with no problems. But [B]once I let go and click somewhere else[/B], the same delay occurs, and I have to sit there holding my mouse button down until it starts to draw on the screen.

This applies to anything else. Lets say I try to resize an object. I hit CTRL+T for transform, it works fine.. then as soon as I start to resize the object with my mouse, it won't actually start doing it for 10 seconds or so... and once it 'kicks in', it works fine until I let go of the mouse button. So the summarize the problem: I click anywhere in my canvas, and my input doesn't "register" for a LONG time, after which, as long as I've been holding the mouse button down the entire time, I can complete drawing normally. But as soon as I let go and click again, same problem.

Even stranger, [B]I HAVE ZERO LAG OF ANY KIND WITH KEYBOARD INPUT![/B]

Now, in trying to debug this problem I've:

[B]- Tried different mice. Same problem.
- Tried using a Wacom pen. Problem happens with that too.
- Upgraded my videocard with the latest drivers. Same problem.
- My Vista64 system has the latest updates, etc.
- Reinstalled Photoshop CS4. Problem still comes back.
- I'm using 2 scratch disks in Photoshop. Doesn't help problem.
- I have OpenGL drawing enabled in GPU settings. Same problem.
- I tried running both 64-bit and 32-bit versions of my Photoshop, and problem occurs in both.
- Photoshop is up to date, and I'm on 11.0.1 [/B]


Like I said, after only 10-20 minutes of using Photoshop, this lag effect starts to appear. Every time, no matter what. I have to close the program completely, and re-open, and the lag goes away.. but then comes right back eventually. I use Photoshop CS4 at work on a (crappier) HP Core 2 Duo computer with only XP 32-bit installed on it, and this problem has never, ever happened once. So I cannot figure out what could be causing this, but it's seriously destroying productivity.

Any advice would be amazing
Thanks all.

Right click Computer icon
Left click on Manage > Device Manager > View > Show hidden devices

Do you see any badly installed devices?