little help with dvd burner

I have a Liteon 451s dvd -/+ burner and I have done the firmware hack to go to 851s and have no problems what so ever and I did this about 2 months ago.
Now my problem is that I gave it to my brother to use for a little while and he is using my external case which is USB 2.0 and that proper usb 2.0 cable and I installed a PCI usb 2.0 card in his machine.
Now when he burns it takes over 2 1/2 hours for one dvd,when I burn it'sroughly 15 - 25 minutes.The red light stays on for me but for him it's going red / yellow / red / yellow constantly?Is this because the buffer is not full?
His comp is a AMD Duron 1ghz,40 gig drive,192 pc133 ram.
Mine is a AMD Athlon 3100+ 512 ram,80 gig drive
A little help would be greaty appreciated.
Thanks

carrach wrote:

Quote:

Now when he burns it takes over 2 1/2 hours for one dvd,when I burn it'sroughly 15 - 25 minutes

Your brother's cpu is too slow. Is his pc usb 2.0 compatiblie? Because if it's not then the speed would be reduced. There have been problems with using external enclosures for internal dvd burners. I'd prefer using a external enclosure via firewire. Check out the LITEON forum at cdfreaks.com.

http://club.cdfreaks.com/forumdisplay.php?s=&daysprune=30&forumid=44

Thanks for replying so fast.

As far as I know it is a USB 2.0 card,in the device properties it's coming up as an enhacned usb port.

Maybe I will put it directly in the machine and see what happens,that could be a problem to?

Thanks for the link to that forum I never new it was there,I check out what they have posted there as well.
Thanks again!