graphics switch seems to kill gpu acceleration

[meeotch]

I've noticed recently that when I switch to "energy saving" (onboard) graphics, and then later switch back to "high performance" (ATI), my applications are noticeably less responsive, and the cpu seems to be pegged all the time. It's almost as if the OS isn't correctly applying gpu acceleration after the switch back. I'm noticing it with web browsers mostly, but also stuff like thunderbird and quicken.

I know that the ATI graphics card is correctly selected, because I'm driving a secondary monitor with it - which isn't possible with the onboard graphics. Killing & restarting applications doesn't fix it... And I even feel like sometimes the issue survives a reboot.

I don't remember this always being the case. And in fact when the machine is running well, I'm still impressed by how snappy it is, despite being several years old. (SSD & maxed-out RAM to thank for that.)

Any bright ideas? (Other than just reinstalling the display driver, which is probably my next stop.)

[SkiBunny]

I have heard complaint by W500 user of a Windows update having that kind of affect. Driver update didn't help him. Ultimately his solution was to buy a second-hand W510. May you have better luck.