Can't enable dma

I can't burn a dvd with nerovision it does the menus and transcoding but when it starts burning onto the disk it ejects the disk saying burn failed, I managed to burn two ISO video files using verbatim cd's, one video with Imgburn and the other with nero burning rom, both played in my pc but wouldn't play in my home dvd player, I 've burned lots of video's and cd's using the same software and media and never had a problem till now, well a few, I've been told I have a dma problem I have tried everything to enable dma I've googled till I can't google no more, and still haven't found a solution, in the bios the burner is set to auto which is the best setting I've been told.
all my drives are sata 1 hdd, dvd-rw, dvd-rom, os winxp, mobo Asus M2V-MX,
2Gb ram,