Heavy cpu usage writing dvds

[snap55 _]

Hi all, I'm using the newest release of ubuntu and think i've got a dma 
issue. The pc has a p4 3.2, 1 gb ram and 2 sata hard drives. The optical 
drives are a liteon dvdrom, a nec nd3500nd dvdr/w, a pioneer dvr108 dvdr/w 
and a liteon 52x cd writer.
Using hdparm -i returns a udma2 as the active mode for all the drives except 
the pioneer which shows udma4 enabled. And using hdparm -d1 or -d0 doesn't 
allow me to enable or disable dma and gives me a HDIO_SET_DMA failed: 
operation not permitted error. The problem I've got is really high cpu usage 
when burning dvds, either copying an image to hard drive and then burning or 
burning an image from the hard drive.
I burned a dvd with 3.8gb of data from the hard drive and it took 28 minutes 
and 15 secs on a 8x rated dvdr and it basically freezes the pc it uses so 
much cpu. I'm using k3b 0.11.17 and thats reports the write speed as around 
1.25x to 1.75x, but I have tried xcdroast with the same sort of time taken.
The mobo is a gigabyte ga-8ipe1000 pro-g using an 865 pe chipset, I would 
think the kernel would be ok with that and wouldn't be using some generic 
chipset driver, but I don't know for sure.
I'm just stuck as what to do next, Ubuntu is really sweet to use :) and for 
sure I'm going to keep on using it despite this, but I really would like to 
fix it.
Any help would be appreciated

Thanks
Paul

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