hi peter what do you mean by tn panels?
Most large LCDs these days made for consumers are TN based. They are cheap with super fast pixel refresh rates but they only deliver 6bit+dithering colour,
vs IPS or MVA/PVA panels which can do full 8 biy colour and above.
8 bit = 16.7 million.
6 bit+dithering = 16.2 million.
The Samsung T260 is a TN based panel for instance. In the past most displays were IPS/MVA based with slow pixel to pixel refresh rates but now that everyone wants to watch HD and games on their monitors - TN is king
and it's cheap. Yeah the sea of TN panels out there is a big disappointment.
I think many HPs and Dells are still IPS based but TN is present in many of the cheap panels - Philips, Samsung, BenQ etc.
I think the more one knows, the more disappointed one gets. A 10 bit IPS based display from HP at 24 inches costs R22,000, put that side by side with an 8 bit let
alone a 6 bit display and you see the difference. For me the colour banding issues on TN panels really suck.