Photoshop brush is lagging on my PC - mystery solved! (at least to me).

I have a decent Windows 7 computer with lots of processing power. Still, I decided to upgrade to a new i7 second generation with overclocked processor, SATA 6 disks and other fancy options.
So, i moved my stuff to the new machine. To my surprise- while Photoshop CS5 worked perfectly fine on my older computer, on this new super-fast beast - brushes were sluggish, lagging badly behind my movements and driving me crazy.
I checked for remedy on internet, and learned that quite a few other people complain about the lag problem.
Recommended by someone solution was to change brush "space" property from default 25 to a lesser value.  It helped to some extent, but it also changed brush characteristics. So, no good. I searched more, and found more postings on various forums.
Desperate, annoyed users tried to uninstall and reinstall drivers, Photoshop itself, Wacom Bamboo drawing pad, trying to debug Photoshop with Adobe support, etc. etc.  Somehow, I did not believe that any of these actions would solve the problem. After all - brush is one of Photoshop's basic options, and if there was a bad driver or other similar problem, it would be addressed in an updated version.
Additionally, I use both  a Bamboo pad, and also mouse. So, surely Bamboo would not affect my mouse performance.
Then, having experience with music recording on my computer - I remembered about latency problem. A similar, annoying lag between the moment one presses a music keyboard key and the moment the sound is heard. And I remembered that latency problems are related to sound card, with different brands and models having a different latency or no latency at all. So, I decided to follow the line of the card - in this case - the video card.
In my older computer I have a Radeon based card. In the new one I had NVidia Ge-force based card.

Instead of trying my luck installing and uninstalling drivers as recommended on some forums - I decided to buy a different card. I bought a simple Radeon card, tossing NVidia altogether.
That was it!!! From the moment I installed new card, all problems magically disappeared!
All works perfectly, and both my pad and mouse feel more crisp, more snappy and more precise!
They work exactly the way i like!

Worth a note is fact that I did not install anything fancy or expensive, but bought a modest card for about $80. So, it is not the fancy card which fixed it, but rather a different chip.
My conclusion is that NVidia Ge-force based cards are "not in love" with Photoshop, and possibly using Radeon cards would solve the problem. I am not a gaming guy, so I can't comment on differences between these brands when playing a game. But - for Photoshop and other editing programs - Radeon rules!
So, if you are one of people affected by this brush lag problem and you use Windows based PC - chances are you can quickly fix it (and by selling your old card you may not lose a penny on this switch!)
Good luck!