[brza]

I have an old G4, 400MHz PPC running OS X 10.3.9
Always, when running OS 9, and even when I upgraded to Panther, I was always able to watch videos smoothly... Of course, if something CPU-intensive was going on, the video play might suffer a bit, but (for example) running a browser, MSN client and a couple other small apps didn't make video play a problem.

Now, virtually always, watching videos in QuickTime or VLC as well as DVDs in the Apple DVD Player, they can jitter a bit. Even if i use the 'renice' command (give processes cpu priority on a scale of -20 to +20) and set VLC or DVD player to -10 which is quite a bit higher in terms of giving it cpu priority, it can jitter.
What gives? My daily/weekly/montly "cleanup" scripts (CRON) run fairly frequently and ran within the last seven days.
I wouldn't be as concerned if it had always been like this, but even in the last 4 or 5 months, DVDs can jitter a little (it's basically like the video goes still for a half second or even up to a few seconds. Once in a while the audio will cut out for less than 0.5 seconds)

Im not stupid when it comes to computers... I'm no genius, but knowing what I know this seems strange. If it was just VLC i'd try other video clients but even watching dvds at times it'll happen.
Two things to note:
-I repaired permissions very recently
-It's definitely not the video files being corrupted to any degree
-I can't boot up to repair the disk as I recently moved and my OS X cd's are in another city. Unless (as i've never done it before) i can make a bootup volume using Toast so that I can run Disk Utility..???

[Big Mac]

You can run the built-in disk utility fsck on the startup drive by booting into single user command line mode (press command+S while restarting) and then typing the command fsck -yf and pressing return. Given the age of your Mac and the fact you apparently haven't run a disk utility in a long time, it's very likely there is substantial hard drive corruption. After this command is run, it will report FILESYSTEM MODIFIED. You have to run the command again until it says HARD DRIVE OK. Oh, and don't worry if it claims the drive cannot be repaired the first time you run the command. After you're done with fsck, type exit and press return to get back to OS X proper. If this doesn't improve your system's performance, you really will need to do an Archive and Install of the OS using Panther discs.

[Todd Madson]

What video card is in that beast? I upgraded (long ago) my G4/400 to a Radeon 8500
and found it was smoother at playing back video. Also try VLC - I find that it performs
better than quicktime on the same system.

[brza]

BigMac: i tried that, It said it appears to be OK on the first go so I'll see how my computer performs after that.

Todd: VLC was doing it too, it wasn't a matter of software, specifically.