I have read a couple of posts on here with people having problems with the 851. I recently got one and started to have the same problems people were describing. Jumpy DVD video playback. Discs that would stutter towards the end. Discs that just couldnt be read etc
I put it down to some dodgy discs but the failures kept getting worse. After reading the forums i upgraded the firmware but it didnt have much effect. I also tried changing the IDE cable etc again all to no avail. There didnt seem to be good advice on just how to fix the issues people were having.
The only one I did see was that someone moved their drive to a new pc and the problem went away. I did the same thing and sure enough it fixed my problem too.
The old PC was no slouch it was a AMD XP 2000 with 768mb of ram running Windows XP and I use the hard disks for video editing so I know there there is no bottle kneck there but there is something on there that didnt get on with this dvd write. I had a 4x sony on there before with no problems.
If anyone has any ideas as to what might be causing the conflict please let me know.