Playback issues w/ ATI 4850HD in SL

[miscbeep]

Hey fellas,

 

I have a problem in OS X ( Version 10.6.6, updated from 10.6.3 iAtkos ). When I play an HD video, say 720p or 1080p, it's choppy every now and then ( VLC and couple of other players ). Also, in YouTube, when I switch to fullscreen, while watching full hd vids - it's choppy/ lags quite frequently ( both Firefox and Safari ). I tried reinstalling the flash player - no difference, since it's probably system-wide ( not only in the internets ). Most notably - I have no problems whatsoever in Windows, playing the same stuff]/b] So I'm pretty sure it's not my GPU, since it's fully capable of playing this content.

Normal screen mode plays smoothly though ( YT ) ! I have qe/ci and all that {censored} enabled. Since this Ati tends to be heatmonster, I already bought a cooling pack Scythe Infinity so I can keep temperatures down.. But I guess that ain't the problem, since Win doesn't have the issues cited above.

 

If someone has a solution or anything I can do, maybe try different kexts or methods for the GPU, or maybe it has something to do with my other components. Here they are, incase that'd help ;

 

MB : ASUS P5LD2 - SE

RAM : 4 x 1GB Kingston @ 667Mhz DDR2

CPU : Intel Core 2 Duo E4400 @ @2Ghz ( stock clocks )

HDD : Brand new 320GB Samsung

PSU : Fortron 400W

 

Thanks in advance !