Apple released a graphics update in conjunction with OS X 10.5.2 which is required for the graphics update. Apple describes the update as “Leopard Graphics Update is recommended for all users and improves the stability and compatibility of your Mac. This update requires Mac OS X 10.5.2.”
Not a lot in the way of details. A restart is needed and it was a 43MB download through Software Update on my Intel MacBook. It’s also available as a 48MB standalone update.
I installed the update on my Intel MacBook. Like the 10.5.2 update my local iDisk displayed a quick compression popup after the reboot. The pop-up hasn’t appeared on subsequent reboots.