jerky scrolling, where's the bottleneck? (1 Viewer)

[Herbs28]

Last week I bought a WinTV Nova USB2 DVB-T stick and moved my main pc downstairs to the TV. I’m a bit disappointed with the results so far. I am using XP (sp2 with all patches and drivers) I have the same issue regardless of software and decoder, including my preffered Nvidia Pure. The same problem is also present using MythTV on Ubuntu. I am finding the image to be slightly jerky, it’s often hard to notice, but particularly obvious with scrolling text. A good example would be the news ticker at the bottom of the screen on BBC News 24. My system is as follows:

Asus M2N32-SLI Deluxe
AMD Athlon 64 X2 4200+
Asus Extreme N6200TC/TD 256MB
2GB DDR2 667
500Gb Hitachi Sata
Wintv Nova S USB2 DVB-T
Creative Audigy ZS
LG32” LC2DB LCD TV

At the moment it’s hard to justify running an htpc if the picture quality is worse than with the tuner on the TV.

Can anyone suggest where the problem is? Should I perhaps be using a PCI tuner card? Graphics card not up to it?

Thanks for reading.

 

[Taipan]

What refresh (vertical scan) rate are you running the LG 32” LC2DB LCD TV at? For PAL TV it should be an exact multiple of 25 (25, 50, 75, or 100). Running the TV at 60Hz will give the effect you describe.

 

[Herbs28]

Thank you for your reply. I believe it's set to 60Hz. I didn't realise this could be the problem, but I really hope it is! I'm at work at the moment but will post when I get home and let you know the outcome with a different rate. Thanks again.

 

[joostzilla]

And what if your TV can only function at 60 hz?

 

[Herbs28]

My TV connects with a PC monitor cable - I assume I can just change the rate on Windows. Is that not right?

 

[joostzilla]

try playing with the deinterlace setting in Purevideo decoder. Sometimes the 'smart' setting gives bad results. 'Automatic' is the better way.

 

[Herbs28]

Taipan you have made my week! Thanks. Seems a lot better at 75hz, not quite perfect but much better. Thanks to you as well Joostzilla, I will look at those settings tonight and see if I can improve it further.

 

[SweMart]

Taipan you have made my week! Thanks. Seems a lot better at 75hz, not quite perfect but much better. Thanks to you as well Joostzilla, I will look at those settings tonight and see if I can improve it further.

75Hz isn't enough, it's better than 60Hz but you should really be using 50Hz.

/Martin

 

[Taipan]

75Hz isn't enough, it's better than 60Hz but you should really be using 50Hz.

I disagree.

As long as the refresh rate is an exact multiple of 25 Hz, then the higher the refresh rate, the better, as you will get less "flicker".

IMHO, 100Hz is best, 75Hz is good and 50Hz is OK ....

 

[SweMart]

75Hz isn't enough, it's better than 60Hz but you should really be using 50Hz.

I disagree.

As long as the refresh rate is an exact multiple of 25 Hz, then the higher the refresh rate, the better, as you will get less "flicker".

IMHO, 100Hz is best, 75Hz is good and 50Hz is OK ....

Well I don't know, football for example is not watchable when I'm doing 75Hz. 50Hz is 100% smooth, and I've never noticed any flickering on my LCD.

I'd say that 50Hz or 100Hz is the way to go.

Or maybe I've got bad eyesight