Up till now, I've used an old Duron system (750mhz) and Nero to burn divx,
avi to DVDs. No problems, 600 disks done. About a year ago, I tried a friend's Sempron system to do this. Almost none of the disks could be read by my DVD players (stand alone). Now, I have an Althlon system (2800)
and the same problem has reared it's head. The stand alone DVD players (high end Sony and a cheap brand) cannot read the disks. Why would this
be happening?? I still have the Duron system, but it's conversion time is very
slow, as you can imagine.

ir probably has less to do with the system processor and more to do with the burn quality (ie the burner, firmware, media, burn speed, etc, etc)

if you don't know the above variables for each system that you've burned discs on then it's going to be very difficult to troubleshoot your problem...

as a general rule you want a good burner (you never said what kind you had) with up to date firmware (also not specified) using quality media (not specified) and burning at the rated speed of that media.

you also want to try not to multitask during burning as that can cause poor quality burns that may not be readable on some playback devices.

sone players/drives are pickier than others so if you're using DVD+R media, it's a good idea to bitset or booktype them to DVD-ROM (if your burner allows...not all do)