X-black version 2

[brado]

I am considering buying a 17" Vaio. I get different answers to which models have the twin tubes. Local Sony shop say that there is no 17" with twin tubes, but the sony shop and others state the A497XP has x- black second generation version got twin tubes? Does second generation x-black also have twin tubes? Sony sites do not state that the A417M has second gen. x-black or twin tubes, but Red-Cloud.co.uk state the it is a secong gen. x-black.
2 months ago, another assistant in my local sony shop, said the the A417M was second gen and had twin tubes, but were not fitted to the first ones.
Can anyone give me the true facts please?

[Skyshade]

17" A series has twin tubes since the day it was born like a year and half ago. Don't worry.

[renoguy]

OK, thought I was up to date, but guess not...

What are "twin tubes"?

[Skyshade]

The backlight tube that lit up the LCD. Two tubes give brighter screen and more evenly distributed light. I don't think there is any LCD less than 17" that uses twin tubes.

[Michael1980]

I am pretty sure that the 15.4 screens use twin lamps as well.
In fact on the old K-series there was a switch on the laptop which activated the second one.