ATSC Card Owners: Come here for Support (2 Viewers)

[Tech Geek]

I haven't tested on XP MC yet but I did find out a few things.

1. The HDTV Superbowl playback with Windows Media Player set for VMR9 is flawless. That includes both 2D and 3D texture modes.

2. 1 of the recordings I made from MP in HD has a frame dropped here or there but it's pretty good..

3. 1 SDTV program I recorded skipped even worse than MP does when watching TV.


#1 tells me it's not VMR9 video playback and the card can handle playing HDTV by itself.

#2 and #3 tell me something stinks in MP or #3 wouldn't happen. The jerking is horrid on #3.

#2 tells me MP is very close to being able to work and with a little time the problem may work itself out... or that's the best the buffering can do.

 

[Commodore 64]

Great job testing Tech Geek.

Is there any way you can get me a sample of the video?

When you see skipping, is it dropping frames, or does the video pause (i.e. video freezes when a quarterback throws the ball and then when it resumes, the receiver had the ball). If it's the latter, it is probably more of a multipathing issue.

Regarding SDTV being worse than HDTV, I had this issue as well with SageTV, when i was using VMR 9 with all other cards prior ro my 6600GT. It doesn't seem to make sense, I know, you would think that the SDTV would be fine and the HDTV would be worse.

Dman thinks he can get your Analog working if you have a fast CPU. You will need to get him the info listed here: http://nolanparty.com/mediaportal.sourceforge.net/phpBB2/viewtopic.php?p=74504#74504

 

[Tech Geek]

Great job testing Tech Geek.

Is there any way you can get me a sample of the video?

Give me another 10 hours in a week and it's no prob! LOL
I'll do some more recording to satisfy a hunch... there is a possibility it has to do with *how* it was recorded rather than the source video resolution. I won't be sure until I can test more.

When you see skipping, is it dropping frames, or does the video pause (i.e. video freezes when a quarterback throws the ball and then when it resumes, the receiver had the ball). If it's the latter, it is probably more of a multipathing issue.

First... not multipath at all. Watch HDTV has no problems on the channels involved and signal strength is excellent. I'm less than 10 miles from most of the stations and only a very weak religious channel causes problems and turning the antenna fixed that. So that's one issue down. I think the ATi tuner is pretty decent as far as multipath goes anyway.

Ok... on the HDTV res stuff I looked at it was a dropped frame here or there. Usually durring motion. I can see that if the video card is to blame so this card *might* be borderline speed wise.

The SDTV was more like the latter but I'm sure it's not the signal.

Regarding SDTV being worse than HDTV, I had this issue as well with SageTV, when i was using VMR 9 with all other cards prior ro my 6600GT. It doesn't seem to make sense, I know, you would think that the SDTV would be fine and the HDTV would be worse.

Well... I think it may be the way VMR 9 renders. Since it's using 2D or 3D textures... that may very well be the issue. When it decodes 1080i it just stuffs it up on the screen without scaling because it doesn't have to. With SDTV res it has to scale every frame unless it alters the output resolution to match. Not only does the card need the bandwidth to transfer the video data but then it has to have time for the scaling. That would make the 10MB/s a requierment to feed data to the card in bursts. Without seeing the guts of the DirectX code I couldn't be sure. If Microsoft wanted to improve it they probably could though.

To avoid this may just require changing the screen res to match the video source. Which may or may not be possible without directly looking at the video stream. I don't know what info VMR 9 provides.
For all I know, Media Portal already does this and it's an entirely different issue. Just throwing ideas out there.

Dman thinks he can get your Analog working if you have a fast CPU. You will need to get him the info listed here: http://nolanparty.com/mediaportal.sourceforge.net/phpBB2/viewtopic.php?p=74504#74504

I'll take a look at it as soon as I can but work has me busy til Saturday and then I may be out of town.

I do think the ATi card has the ability to encode MPEG in hardware though. It would just require the ATi NDA and all that goes with it to find out how to use it. So that means I'll need to be happy with software encoding for some time. LOL

I have a Sempron 64 2600+ and if I overclock it even a little I should easily make the suggested speed of 2.8GHz. People are pushing these above 3000+ all the time.

 

[Tech Geek]

(I edited this due to leaving out something important and I decided to fix the numbers I made a shortcut on)

I checked the specs on the graphics card and there was some conflicting info but here goes.

The RAM is between 400MHz and 500MHz DDR2 depending on what I read. The PRO version is 600MHz. <edit> The pro version is actually 800MHz</edit>

The current specs on the manufacturer website say 500MHz as is my card (according to ATi Tools) but they may have made some with 400 or 450 that went out to reviewers. (I think the problem is the author of the articles) The memory interface is 128 bit.

So.... memory bandwidth should be one of these:
400 * 2 * 128 / 8 / 1000 = 12.8GB/s
450 * 2 * 128 / 8 / 1000 = 14.4 GB/s
500 * 2 * 128 / 8 / 1000 = 16 GB/s
600 * 2 * 128 / 8 / 1000 = 19.2 GB/s
800 * 2 * 128 / 8 / 1000 = 25.6 GB/s

For those scratching their heads... the first number is the RAM clock in MHz, the 2 is for the DDR (Double Data Rate) which transfers data twice per clock cycle, the 128 is the memory width on the card in bits, the 8 is the number of bits in a byte and the 1000 is the conversion from Mega to Giga.

Even the lowest should be enough for HDTV.
My memory is supposedly overclocked to 513 for 16.416GB/s.

That makes the problem I'm having software related. Scratch one more possibility!

Now... those numbers don't include real world things like memory refresh and other things that cut performance but there's enough extra bandwidth there to make up for it.

If I didn't mess up the formula (entirely possible) then any card with DDR 400 or faster memory should be sufficient.

I have no idea where someone got just over 8 GB/s unless they forgot that DDR doubles the transfer rate... in which case I wouldn't trust them much as a source of information. That or they calculated with a 64 bit buss... which there seems to be some confusion about. The X1300 doesn't have the ring buss controller upper models have that people are saying cuts the true buss width in half.

 

[Tech Geek]

Perhaps I should rephrase something...
Any card with DDR memory clocked >= 400MHz and a 128bit or wider buss width should be sufficient. In theory anyway.

 

[Tech Geek]

Well, the USB receiver for the Remote Plus that came with my tuner went kaput the first night and CompUSA won't just let me exchange just that part. I have to disassemble and rebox EVERYTHING. I'm probably just going to return it rather than exchange it since they made me mad. Since I can't find it in stock anywhere else I'm going to be HDTV tunerless for a while unless I just give in to a swap.

 

[Tech Geek]

BTW, after some looking... the formula I used is wrong. DDR 400 is 200MHz * 2 data transfers per clock rather than 400MHz with 2 transfers. So all those bandwidths would be half of what I posted. In other words... it takes a card with a memory buss of 625 or higher to achive the bandwidth Microsoft wants for HDTV in VMR9 with a 128bit memory grahics card.
With a 256 bit card it would be half that.
As far as I could tell, if you want to go with passsive cooling and HDTV you must go 256bit on the graphics card to meet the Microsoft spec.

That should probably be in a guide somewhere.

The *only* passively cooled card under $200 that meets the 10GB/sec requirement (that I found) is the HIS Hightech H130H512N Radeon X1300 512MB 256-bit GDDR2 PCI Express x16 CrossFire Ready Video Card priced at $120.

http://www.newegg.com/Product/Product.asp?Item=N82E16814161167

 

[Commodore 64]

I use a passivley cooled 6600GT, from Gigabyte I paid 166 for the AGP version, the PCIe version is now 155. Also note that the nV Silencer aftermaket HSF oare dead quiet and move a lot of air.

PCIe passive 6600GTs:
http://www.newegg.com/Product/Product.asp?Item=N82E16814125175
http://www.mwave.com/mwave/viewspec.hmx?scriteria=AA41200

Tech Geek: I wish I had a spare 6600GT that I could send you so you could test it with your hardware. I know I had stuttering with SageTV and MediaPortal with almost all Digital OTA stuff until I got one. The troubling thing is that the 9600pro and 9700pro, especially should have been able to meet the 10GB/sec criteria with no problem. I still can't figure out why I couldn't get the 9700pro to work.


http://www.avsforum.com/avs-vb/showthread.php?p=7129165#post7129165 This guy is having stuttering even with his 6600GT and a Fusion Lite card. Man what a crapshoot this can be!

 

[Tech Geek]

I use a passivley cooled 6600GT, from Gigabyte I paid 166 for the AGP version, the PCIe version is now 155. Also note that the nV Silencer aftermaket HSF oare dead quiet and move a lot of air.

PCIe passive 6600GTs:
http://www.newegg.com/Product/Product.asp?Item=N82E16814125175
http://www.mwave.com/mwave/viewspec.hmx?scriteria=AA41200

Tech Geek: I wish I had a spare 6600GT that I could send you so you could test it with your hardware. I know I had stuttering with SageTV and MediaPortal with almost all Digital OTA stuff until I got one. The troubling thing is that the 9600pro and 9700pro, especially should have been able to meet the 10GB/sec criteria with no problem. I still can't figure out why I couldn't get the 9700pro to work.


http://www.avsforum.com/avs-vb/showthread.php?p=7129165#post7129165 This guy is having stuttering even with his 6600GT and a Fusion Lite card. Man what a crapshoot this can be!

Ok, the first card you linked to on the Newegg site.... 128 bit but memory clock of 1120MHz. All I noticed was the 128 bit and core clock of 500MHz. Oops... my bad. But some specs are different on the 2nd link.

If a 9700PRO doesn't work I'd say it's a DDR clock speed issue. That has DDR 400 if what I found is right and it's peak bandwidth rather than overall bandwidth that is the issue. Which means that 256 bit and DDR 400 may not solve the problem. Then it's a RAM clock over 625MHz.
I'd say it's actually lower and Microsoft is playing it safe.

Some people have memtioned setting the PCI latency and all sorts of things in an attempt to get this to work. I'm sure that can have an effect but I don't think it's the real problem.
It's gotta be related to decoding and buffering somehow and the fault lies with Microsoft It's not the tuner, it's not the video card... it's Microsoft.
Rather than spend a dime rewriting their code they just bump the required specs and say upgrade.

If I were to guess I'd say that instead of sending data to the card at a constant rate and using buffering to keep data ready for the card they are bursting blocks of video to the card as they arrive and if the card is still busy from the last burst it dumps the next block. Why it bothers lo-res more than hi-res I'm not sure. Perhaps block size or receive buffer size have something to do with it. Lo-res may have larger block lengths (in frames) so more frames are dropped when the card is found to be busy. That would be much jerkier than hi-res that would drop a few frames here and there.

 

[Tech Geek]

After some additional reading I'd say that the VMR9 issue isn't just a memory bandwidth issue but also a CPU use issue. The higher the CPU use the more sensitive it is to the bandwidth. And MediaPoral uses a lot of clock cycles just sitting there.