708A + Nero 6.3.1.25 + winxp sp2 = slow burn?

I was using a prior version of Burning Rom (6.1.x.x) and it chugged along nicely w/ winxp sp1. 4x dvd-r would usually take about 15 minutes on my plextor 708-A. This combination worked for over 1 year w/ over 200 successful burns (no coasters).

Last week I decided to upgrade to winxp sp2 and found out that my older version of Nero would no longer be compatable, so I got v. 6.3.1.25 and installed it.
It burns my 4x but now takes over 45 minutes to complete a full burn.

Other than installation of sp2, nothing else has changed. What gives?

Please help. Thanks.

Mike.

You should get UDMA2, if not the check this out: http://club.cdfreaks.com/showthread.php?t=101616