24fps on PHD8 via HTPC

[rsjt]

Not sure if this or the computers forum is the best place to ask this but the new nvidia beta graphics driver now allows custom resolution settings and timings with my 8600GTS graphics card. So I was going to try and get my Blu-ray HTPC to deliver 24fps on my Panny 50PHD8 via the VGA input (currently I use the HDMI input with 1280x720 at 60hz but do notice a bit of judder here and there).

I was going to try and set the graphics card to output 1366x768 at 48hz to feed into the PHD8 via the VGA input, but I just wanted some advice before I started messing around too much and end up damaging the screen. For example as an alternative should I do:

(i) 1920x1080 at 48hz and let the Panny downscale to native res
(ii) 72hz instead of 48hz
(iii) be precise and do 23.976x2 = 47.952hz. Only problem is that this is out of the vertical scanning range in the PHD8 manual (48-120hz).

Anyway grateful for any advice/help anyone could give me.

 

[choddo2006]

1. No, use 1366 (1368?)x768 @ 48Hz
2. Worth a try. I can't see any diff between 48 & 72
3. Hmmmmmmm. Not sure.

 

[Flimber]

Which driver are you using ?

 

[rsjt]

Hi

I'm using the latest drivers from the nvidia website

Version: 175.16
Release Date: May 16, 2008
Operating System: Windows Vista 32-bit

Cheers

Ryland

 

[RDarling]

I am currently doing this with my 42" PHD8 so am using 1024 by 768 as the resolution into the VGA port.

I experimented with different timings in powerstrip using precise multipliers as well as 24, 48 and 72Hz. All results were pretty good compared to 60Hz.

I found that it was 23.976 that eliminated judder entirely. I found very slight judder on 48 and 72Hz

Clearly this is a strange result as the panel should not accept this resolution - perhaps there is some internal doubling going on and somehow this is marginally more precise than Powerstrip?

I use an ATI card so NVIDIA may be different. You can try Powerstrip before you buy and it may give you more control over the timings.

Cheers

Robert

 

[rsjt]

Thanks Robert. I'll definitely try setting 23.976 with the nvidia card. If that doesn't work I've got an ATI card in another PC which I think is HD-capable. So I might try using powerstrip with that as I don't think powerstrip works with the 8 series nvidia cards. Thanks for your help.

Ryland

 

[Barcoing Mad]

Worth considering running ReClock alongside Powerstrip - gives you more control over refresh rates for judder free playback.

 

[rsjt]

Well after lots of playing around I've ended up using the ATI card from my other PC (HD2600XT) with Powerstrip. I've tried lots of settings but I've ended up setting 1920x1280 at 23.979hz (I couldn't fine tune it exactly to 23.976 in powerstrip). The PHD8 is reporting 24hz so I guess it must be converting this to 48hz internally. Bottom line is that this is giving me judder free playback now and I'm really happy with it. I might have a further play to try and refine things and have a go at getting native resolution at 23.976hz. In particular I might try using reclock though as I'm using Vista I wasn't sure reclock will work with it as the latest version seems to pre-date Vista ?

Anyway thanks for all your help guys. This has definitely avoided having to upgrade my screen to get decent Blu-ray playback so you've saved me a couple of grand at least !