[mythtv-users] High end, state of the art Myth Frontend

[Andre Newman]

On 19 Sep 2013, at 01:24, Joseph Fry <joe at thefrys.com> wrote:

>>> Well, I've upgraded from a 9400GT, to a GT220, a GT430 (ugh) to a GT640 and each step of the way picture quality has improved in various ways. Yes I've gone back and tried to old cards (this week actually) and yes the newer ones are better, my girlfriend has commented "what's wrong with the picture" when I went back to the GT220 last week trying out another old LGA775 board that doesn't seem to like the GT640, doesn't like the 220 much either!
>> 
>> now we're entering the placebo realm….

Not quite, the shiny new GT430 I bought (it's new so it must be better) was kicked out after a week and the GT220 put back, at least until the drivers improved although eventually I bought a 640 to get glitch free pictures with lower chroma noise like the 430.

>> 
>> Must be the quality of the digital cable you're using , the signal is purer !

Now, now, I'm not one of those directional copper, valve amplified, green felt tip pen wielding audiophiles ;-)


>> 
>> Decoding will be identical between all those cards, and Advanced 2X
>> will be identical to all the cards supporting it.

I agree that there appears to have been no difference in de-int other than can it keep up.

>> Now cards like the GT4xx or GT6xx have extra post-processing options,
>> but they aren't enabled by default.

I have vdpauhqscaling which has a marked effect on the 640, I don't remember if the GT220 had this feature and I haven't watched any SD since re-using it.

>> 
>> I'm willing to bet that if you did a bit for bit comparison between
>> all those cards, using the same options, you'll find identical data.
> 
> I was thinking the same thing at first so I had to look it up...
> Nvidia likely tweaked the design of the silicon between generations:
> http://en.wikipedia.org/wiki/Nvidia_PureVideo  The GT640 is a 5th Gen
> chip, so it may have improved a few things, but the 220 and 430 should

Perhaps as the 430 was clouded by glitchy playback but I did many swapout tests with the 220 at the time of that purchase.

The main differences were in chroma noise reduction but subtle good noise reduction not the usual kind found in LCD TV setup menus, also improvements in SD scaling.


> be identical except, perhaps, in the resolution and framerates they
> can support.
> 
> But most likely the differences, to be perceptible, are related to the
> vendor's default settings for color gains, contrast, etc rather than
> the capabilities of the silicon.

Everything is calibrated each time and also every 6 months or so, when the bulb ageing changes the colour balance. So this shouldn't be a factor.