BleepingComputer.com: Problem with colour on applications

Hello

I have been using Photoshop CS4 for a long time on my laptop which has Vista Home Premium. However, two days back, I noticed that my brush strokes on the photoshop canvas was appearing like a gradient, from the top corner to the bottom. Originally, I thought this was because of an effect I used, but upon testing it on a blank background, I still noticed the problem was there. And here I was thinking, that this was a problem with photoshop. Here are some screenshots.

http://i56.tinypic.com/esjihv.jpg
http://i51.tinypic.com/jhc8oy.jpg


I then set photoshop to default settings, with no luck at all. Then, I did a system restore, and when that didn't help, I tried to reinstall, which also didn't work. But then I had the crazy idea that this wasn't photoshop's problem, so I tried to do the same thing on MS Paint. I just drew a line from the top corner to the bottom, and guess what? Same thing! To make sure of this, I opened up MS Word, and made a rectangle, which confirmed that the colour DID appear as somewhat of a gradient. So I thought maybe, this was a problem with my laptop's screen. So, I connected the display to my TV using an HDMI cable, and there still weren't any differences.

So, I tried disabling my display driver, an ATI Mobility Radeon HD 4670. The problem was still there, on MS Word, Paint and photoshop.

I am very involved in digital painting, and with this problem, I really am having difficulties to do anything. All help would be greatly appreciated.

My laptop Specs:

Dell XPS 1640
Processor Intel Core 2 Duo P8700 @2.53 GHz
4 GB DDR3 RAM
Windows Vista Home Premium service pack 2 32 bit
ATI Mobility Radeon HD 4670