Any help appreciated on this one! Working on an MSI 790GX-G65 with a Phenom II x2 550BE that I've unlocked to a Phenom II x4 B50. Everything works fine with the exception of HD video that stutters even when using VLC Media Player. The unusual thing is that when the CPU is stressed with Prime95 playing the HD video at the same time it's smooth with absolutely no stutter. I've turned off power saving features in the BIOS but just can't nail the problem and don't really want to run Prime95 just to watch a HD video!
Have you check the power management settings in windows, particularly the Minimum Processor Sate. Power options > change plan settings > change advanced power settings > processor power management > minimum processor sate.
^^ Try this, turn off core parking I did a thread on how to do it http://forums.bit-tech.net/showthread.php?t=187645&highlight=Core+parking
Really doubt this has anything to do with core and if they are parked or not. As he said, the CPU is not under stress and you don't need many cores for HD video. I did have some stutter playing BF3 on 680GTX and eventually solved it by increasing allowed power to the card through MSI Afterburner. Apparently there is a fault of some kind in the Nvidia profile since 309 or some such. You could try raising the power output to the card. Set it back to default if it doesn't work. Same with Core Parking and pretty much anything you try. Windows Vista and up handle core allocation just fine.
Almost! Had to 'optimise' video playback in the Mutimedia settings tab. Completely ridiculous though. Installed a fresh copy of Windows 8.1 and it defaults to not playback video at optimal settings!?! Just don't get the idea of power saving when the extra performance would benefit the experience of using Windows. Why it defaults to this setting is beyond me given the hardware I installed the OS to... Quad Core, 8GB Memory and a 5770 Video Card.
