Thank you again for the helpful tips.

First, on the issue of VRAM size of Mac mini G4's: On eBay and similar sites, the Mac mini G4's with 64MB VRAM are sold with the statement "it can play 720p movies" And more interestingly on Mactracker (an app which lists all Apple hardware) Mac mini G4 with 32MB VRAM is listed as "obsolete" whereas the one with 64MB VRAM is listed as "vintage" So I believe there should be a difference because of the VRAM size, though I never had the opportunity to test by myself.

Derringer: How do you display the Video bitrate of a movie in MPlayer? In my installation, the MPlayer shows only the audio bitrate but not the video bitrate. It either shows the video bitrate os 0 or doesn't show it at all. The audio bitrate varies between 192 - 1524kbps among various movies.

Many movies have "DTS" audio in addition to the AC3 audio. When a movie has only DTS and no AC3, the Media Player tries harder to convert it to AC3 or Analog. So I try to choose AC3 audio whenever it's available in a movie in XMBC or Plex in Mac OS X. Is there such a setting in MPlayer?

How do you play a video from RAM? How is it done?

How do you measure the RAM speed?

Lastly, I remember overclocking to 1.58GHz was not recommended in the Mac mini G4 Overclocking tutorial, because of the heatsink capacity. But according to what you say, an OC to 1.58GHz looks quite fine and preferable.