Thanks for the credit on the fix tjc, I'm so proud, my first bug!

Ok for HD playback I briefly flirted with XvMC but alas, had the audio dropout with the OSD that I just couldn't stand. I was all ready to go out and blow some more money on a faster processor when I came across a little tip from Human. Using libmpeg2 as the decoder and onefield as the deinterlacer I get good playback on an A64 3000+ at 1.8 ghz. Setup like this I get around 75% cpu usage (with 25-15% idle) when watching 720p live tv . The best with any other decoder setup was 85% (with less than 10% idle), and most were 85-95% and no idle.

So if you haven't tried it yet, give libmpeg2 and onefield a shot.

_________________
MythTV box: Opty 170, MSI K8NGM2-FID, 1.5 GB PC2700, Seagate 7200.10 400GB, Lite-On Combo drive. PVR-150, HDHomeRun. Antec Sonata, Freezer 64 Pro. Oh so quiet.

modemboy',
from your findings, using your A64 3000+ setup would you agree that my lowly XP2600+ (32-bit) is never going to be able to cope with HD using this libmpeg2 and onefield setup?

I don't mind so much having to scrap my motherboard and CPU (memory, video card, etc, etc) but I was worried that I was going to need a super fast dual core based system. Of course, it would have been wonderful if my XP2600+ was able to handle it, and initially with XvMC I thought that it was, but like you I found the audio dropout (and video stutter in my case) to be unbearable.

Anyway, I will go and start researching motherboards again. Perhaps, eventually I can use my old XP2600+ system for a separate backend and buy some big disks and stuff that away in a cupboard somewhere. At least it won't feel like I am throwing money at this project all the time , at least I will get added value out of it.

BTW do you know if MythTV actually takes advantage of the 64-bit capabilities of the A64 or does it just run 32-bit instructions at the time? I assume KM is always installing 32-bit OS, but I have looked into this,

Kevin

Actually I think you might get away with HD playback with that setup. Check out these posts here:
http://www.silicondust.com/forum/viewtopic.php?t=2422

The relevant part: "I can actually watch hd material on my athlon 1700xp with another nvidia 6200 and that box has 1 gig of memory in it."

I think Knoppmyth is strictly 32 bit...

If you do decide to upgrade, I highly recommend the nvidia nforce 430 chipset (also know as the geforce 6150). Most boards are microATX, have onboard DVI, VGA, Component Video, optical and coaxial digital audio, perfect for a frontend. There are socket 939 and AM2 versions, and you can get a dual core AM2 processor for $100-$120 retail now. Very much the best bang for your buck IMHO.

_________________
MythTV box: Opty 170, MSI K8NGM2-FID, 1.5 GB PC2700, Seagate 7200.10 400GB, Lite-On Combo drive. PVR-150, HDHomeRun. Antec Sonata, Freezer 64 Pro. Oh so quiet.

thanks for the pointer 'modemboy'. Actually I have been spending the past week or so following that thread. As far as I can figure out I have followed all the correct steps but I don't see any CPU% reduction whatever.

I don't know why. I am only using 512M ram, but from what others have told me this should be adequate. I am using a 6200TC video card, but it is AGP8X, so I dont know if that is a factor. According to the logs it is being set up for 8X

I have tried a number of clean installs of R5E50, and have installed the 9746 driver again each time.

Nothing works for me, and I don't know why. It sounds like I *should* be able to make it work from that post you pointed me to, but I can't figure out what I am doing wrong. I am setting up for UseEvents and setting the correct switches in nvidia-setings.

Only thing I did wonder is if the nvidia-settings which I configure in the KnoppMyth desktop - do these get saved to some config file so that when I switch back to MythTV it picks up the new settings? When I drop back out to KN desktop I can see the settings are stuill there, but I am worried that MythTV might still not be picking them up.

Someone suggested that the old audio codec on my board could be a CPU hog, but if the CPU drops to 20% with XvMC doesn't that rule out the codec?

Only other thought is that I am not actually viewing HD on a HD screen at the moment, I am using a CRT monitor at 800x600 resolution, so maybe there is some CPU cycles associated with that,

If anyone has any ideas please let me know, it might just save me a few hundred bucks,

Kevin

I just tested my Asus M2NVP-VM, A64 3200+, 512Mb DDR2 533 RAM (128Mb of which is set for the onboard nVidia 6150 video) and found my best HDTV playback occurs when I use Bob deinterlace and set "Preferred MPEG2 Decoder" to Standard (yep, just Standard). I get a couple of very minor skips when the OSD is up, otherwise playback is very smooth. I haven't done extensive testing with this configuration, but so far it looks very promising!

I'm rather new to AMD-based systems, I hope this gives you some point of reference.

EDIT: Sorry, should have mentioned I'm running R5D1, and that my CPU utilization sits at ~55% with this configuration. Much better than the 98-100% I was seeing with other combinations. Also, I have set Options "UseEvents" "True" in my XF86Config-4 file /EDIT

I have a Sempron 3100 and went from 70-90% CPU (on a 10% overclock!) when watching 1080i to 20-30% CPU (not overclocked) by upgrading to the latest nvidia drivers and adding the following to my xorg.conf (in the "Device" section after the Driver "nvidia" line):



I can't remember where on the Web I found that stuff, but it worked like a charm. You may have to change that "NvAGP" value to something other than 2... I started at 1 and got low CPU but choppy playback. 2 worked perfectly.

I'm using XvMC and Bob.

'punditguy',
thanks for the suggestions, but as with all my previous attempts I still don’t see any CPU% drop, I am still at 95% when pop-ups are on the screen, video and audio is stuttering badly.

Here is a copy of the ‘Device’ section of my xorg.conf ..

Section "Device"
Identifier "Card0"
Driver "nvidia"
VendorName "All"
BoardName "All"
Option "UseEvents" "True"
# Value Behavior
# 0 disable AGP
# 1 use NVIDIA's internal AGP support, if possible
# 2 use AGPGART, if possible
# 3 use any AGP support (try AGPGART, then NVIDIA's AGP)
#
# Option "NvAGP" "2"
# Option "NvAGP" "1"
Option "NvAGP" "3"
Option "RenderAccel" "1"
EndSection


NOTE, for the xorg.config I also tried NvAGP values of 1 and 2.

From KnoppMyth desktop I have set the following (based on what I have read from other posts for users who have been successful) ..

X Server xvideo settings:-
================
Video Texture Adapter -
Sync to Vblank ENABLED

Video Blitter Adapter -
Sync to VBlank NOT Enabled

OpenGL Settings:-
===========
Sync to VBlank NOT Enabled
Allow Flipping NOT Enabled


In MythTV TV Settings/Playback ..

Deinterlace playback: ENABLED
Algorithm: Kernel (also tried Bob 2x and one field)
Enable OpenGL vertical sync for timing: NOT Enabled
Enable Realtime priority threads: ENABLED
Extra Audio Buffering: ENABLED


Does any one have any idea what else I could try?

Thanks,

Kevin

For reference, here is a link to the Nvidia support site that explains all the xorg.conf settings ..

http://us.download.nvidia.com/XFree86/L ... dix-d.html

Kevin

'punditguy'
I set up the themes to Blootube for both screen and OSD, which you told me is how your system is set up. This made no difference to the CPU%

Next, I tried forcing my system to use the nvidia agpgart, as per the following post:

http://mysettopbox.tv/phpBB2/viewtopic. ... ight=nvagp

After doing this and rebooting I checked using ..

lsmod | grep agp

and it confirmed that it was now using the nvidia one (previously lsmod told me it was using via_agp)

So, full of hope and expectation I pressed the watch TV button and stood back and ..

NO DIFFERENCE, still lots of stuttering with the pop-ups

This is driving me nuts. There must be a solution out there somewhere.

You told me that you are using:

Sempron 3100
nVidia 6600 GT, AGP 8X
single 300GB IDE
R5E50
1.0-9746 nvidia driver

not too different to my system:

Athlon XP2600+
6200TC AGP 8X
single 80G IDE
R5E50
1.0-9746 nvidia driver

so I would have expected to see similar results, alas not.


Only thing which I have not mentioned in this thread is that my frontend and backend is in the same box - is this the same for your setup?

Also, can you tell me which motherboard you have, in particular I am interested in which chipset (mine is Asus A7V8X, VIA KT400)

One last thing I want to check is that the refresh rate specified in the modelines is evenly divisible by the frequency specified in the modelines (or something like that). That is one thing which I have not looked at yet.

If that doesn't reveal anything I am completely stumped. Almost a month into this project and I am still banging my head against the wall

Kevin

this is the modeline article that 'whitepines' pointed me to ..

It's interesting that the stuttering problem is just the same, even if I uncheck the 'deinterlace' box in playback setup screen.

So I guess that it doesn't matter if I use libmpeg, standard, bob, one field, or whatever. If I am still at 95% CPU without any deinterlacing then the problem must be elsewhere,

anyone got any ideas?

Can anyone help me with the modelines? I have a standard Samsung CRT monitor at the moment, I loaded KM with the 'tv' option so it is defaulting to 800x600 screen size. I just wanted to make sure that I comply with the suggestion in my previous post ..

"make sure that your modeline is using the correct frequency. It must be a multiple of the source video framerate, for me that is 30, or 1/2 of the NA 60.
"

however I am not sure how to set up the modeline to acheive this,

I have looked on the Nvidia support site and found the following article but I still can't figure it out ..

http://us.download.nvidia.com/XFree86/L ... dix-j.html

My current 800x600 modelines look like this ..

Section "Monitor"
HorizSync 30.0 - 50.0
VertRefresh 60.0
ModeLine "800x600" 36.0 800 824 896 1024 600 601 603 625 +hsync +vsync
ModeLine "800x600" 40.0 800 840 968 1056 600 601 605 628 +hsync +vsync
ModeLine "800x600" 50.0 800 856 976 1040 600 637 643 666 +hsync +vsync
ModeLine "800x600" 49.5 800 816 896 1056 600 601 604 625 +hsync +vsync
ModeLine "800x600" 56.3 800 832 896 1048 600 601 604 631 +hsync +vsync
ModeLine "800x600" 68.2 800 848 936 1072 600 601 604 636 -hsync +vsync


thanks,

Kevin

I was thinking on this, and when you did the upgrade, did you first remove the auto-startup script to install the old version?

from:
http://mysettopbox.tv/phpBB2/viewtopic. ... highlight=

try running /usr/bin/nvidia-settings to check maybe?

Here's my x.org where I added the use events line. other than that, it's stock from the nvidia config

eeek, no

However I did not receive any errors during the install of the 9746 driver. also, in nvidia-settings it sems to confirm that I do have the new driver.

Maybe though there is some hangover from not having run those three steps.

I will give this a try. I am going to kick myself for missing this if it does fix it,

Kevin

Ok, so I did the 'update-rc.d -f install....' stuff this time before I installed the driver (actually immediately before the 'sh NVIDIA-Linux...' step)

Unfortunately it didn't help, I still see the same problem.

So, unless anyone else has any ideas, I think that I have no choice but to admit defeat and retire my Myth box to the dusty corner of some old cupboard

After nearly a month of frustration with this thing, I'm finally ready to jack it all in.

Thanks to everyone who has helped me, I really appreciate you taking the time out to help me. Maybe there is something wrong with my hardware, maybe this setup was never meant to work for me.

Not sure when I am going to get back to building Myth box, I have to start saving for the new hardware. Actually, I could now spend time instead trying to get my DLINK usb wireless dongle to work, that loks like being another long saga,

Kevin

Hello all,

Just wanted to add a happy ending to this thread.

I had a theory that the PCI bandwidth was insufficient to handle 1080i, so I bought an AGP FX5200 and installed it in my old P4 1.8GHz with 512Mb of memory. After fixing the XvMC problem on a default install of R5E50, and adding the options "NvAGP" "1" and "RenderAccel" "1", I was rewarded with beautiful hi-def silky smooth playback!

There is still a problem with 1080i when watching LiveTV (choppy still), but I'm just happy that I can playback my recorded hi-def programs!

Hope this helps,

Tim