Copyright 2009-2012 by djg. All Rights Reserved.

Wonky Gibbon Ramblings



Flickery HD on Freeview 0

Posted on July 03, 2012 by danny

So I’ve been having problems with HD on FreeView for ages. Sometimes it would just about work but other times the screen would go black for up to 4 seconds at a time – though the audio would continue uninterrupted. Some channels seemed worse than others – but then a channel that had been okay one day – would turn to crap the next.

I have top end Black Gold tuners and a more than adequate graphics card – so I put it down to reception. It had the feel of a reception problem, comments on other forums seemed to corroborate that, and I noticed that MediaCenter reported the signal strength as being around 66%.

However – I had an SSD failure last week so I had to replace the drive – I usually move the pagefile to a spin disk – but this time I left it on the SSD.

HD works. No flickering.

I never considered it would page – I thought 2GB RAM would be enough. But clearly it is not and the system is using the pagefile.

If it really is paging video data, which as we know is lots of data, it could wear the SSD out fairly quickly, even with the levelling algorithms they use. I shall investigate the quantity of traffic and report back…

Upgrading Media Center to HD 1

Posted on August 01, 2011 by danny

I’ve slowly been adding the ability to handle HD content to my media center of late. As usual, the machine is well underpowered so it always stretches the components.

I started by adding a Black Gold BGT3620 Dual HD tuner. This supports both Freeview and Freeview HD (as well as analogue and cable). Setup as always was very easy and it works with Windows 7 Media Center seamlessly. This is an expensive high end card. As mentioned in other posts, the key difference between this and other tuner cards is that Black Gold do a lot more of the stream processing on card rather than relying on the CPU to do the processing. This allows the rest of the machine to be a rather lower spec and prevents the CPU becoming a bottlekneck.

I then added a Samsung UE40D5000 40″ LED TV (which is excellent incidentally – the blacks are … err … very black!). This has a Freeview tuner built in (but not Freeview HD). I also didn’t go for any of the built in internet / iplayer gizmo’s that some of the more expensive Samsungs go for – on the grounds that since it’s attached to a PC – the PC is doing all of that.

Once the TV was connected up and the output from the graphics card altered to the new resolution it became clear that the move up from 720×576 to 1900×1080 was clearly a step to far and at this resolution the media center really started to struggle. SD content was ok, but any rapid movement in the HD content it could not cope with becoming stuttery and blocky. The Graphics Card, a GeForce 6200LE for PCI-E clearly couldn’t cope. Given this was launched in 2004 perhaps this isn’t surprising but it’s worth mentioning because until 2011 it was still being sold as a budget card around the £25 mark. It had a fill rate of approx 700 megapixels / second.

Taking the card out and relying on the onboard graphics capabilities of the motherboard, a Gigabyte GA-946GMX-S2 i946GZ actually improved performance which was unexpected. But then a new budget card was dropped in, the GeForce G210 (£27 inc Vat), launched in 2008. With a fill rate of 4.1 gigapixels / second, clearly much quicker. The result? HD playback is now flawless. As always I buy fanless cards for the media center – I want to listen to the movie, not the machine.

Along the way I also answered the question “Do graphics cards with hdmi output sound?” – Answer: In 2011, yeah, probably. Going back four or five years this used not to be the case, a card with HDMI may well not have had audio, indeed may not even have provided a connector to grab the audio from the motherboard or soundcard – but these days this would appear no longer to be the case, if a budget card like the G210 has onboard digital audio output to the HDMI cable, it seems likely that most other graphics cards will do as well. In the world of PC based media centers and gaming on TV’s this was probably an inevitability. A card supporting HDMI and not supporting audio is just, well, a bit pointless really.

My one remaining problem? The plastic surround on the HDMI cable is too fat preventing the connector from fully inserting into the HDMI socket of the card (it catches on the PC case). I either need to cut the extra plastic off OR buy a flatter one. Grrrrr.

Next I installed a Samsung Bluray drive to replace the existing DVD drive. This came bundled with CyberLink’s Powerdvd software and supports that products “TrueTheater” upscaling technology to upscale SD content on DVD to something approaching HD. You can use this in a split screen before and after mode to look at the changes. I turned off it’s colour lightening setting whilst setting the sharpening to the middle setting and tested it on some scenes from “The Lord of the Rings : The Two Towers” and the improvent is remarkable – definately no need to buy the Bluray version of the movie. The only slight niggle here, is that whilst the standalone version of Powerdvd works flawlessly, the embedded version that sits within MCE doesn’t quite display full screen leaving a black border.

So the system currently stands like this:
Gigabyte GA-946GMX-S2 i946GZ Socket 775 onboard VGA 8 channel channel mATX
Intel E2160 Socket 775 Pentium Dual Core 2×1.8Ghz 800FSB Retail Boxed Processor
Asus GeForce G210 SILENT 512MB DDR2 DVI VGA HDMI Out DirectX 10.1 Low Profile PCI-E Graphics Card
4GB Kingston DDR2 RAM

Next time out – I’ll be getting surround sound sorted out.

Not all TV Cards are Created Equal 2

Posted on December 30, 2009 by danny

Question

So, what is the difference between one TV card and another; given you can buy dual tuner cards that will allow you to record two channels of DVB-T for next to nothing – what do the more expensive cards give you?

This has been bothering me since my last post on my Windows 7 MCE. Indeed its been bothering me ever since I did my original tests with Windows 7 RC1. That build seemed rather better in terms of responsiveness than the actual Windows 7 one did. There are of course lots of differences between the systems. One was RC Ultimate edition, the other the released Home premium, different disk drives as well – but one thing I had overlooked was the TV Tuner Card. Due to a problem with the Black Gold Signature cards (you can’t use two together under Windows 7 as you could in XP), when I built the final system I replaced the single Black Gold card I had used in the RC with a new Dual Tuner card from Peak.

In terms of the recorded programs, the Peak card has produced excellent results – but in this very underpowered, single core setup it has struggled to encode data when the machine was doing other things such as fast forwarding a different program being watched simultaneously.

Putting the single Black Gold tuner back in to the system, revolutionised it. It’s as quick as Windows MCE 2005 ever was.

Answer

And that’s the difference, the more expensive cards do much more of the encoding effort, relieving the burden from the CPU. Freeing it up to be responsive to user requests (such as “Fast Forward my program please” or “can I see the Guide whilst my program still plays please”) without crashing.

Conclusion

Which brings you to a simple choice:
It’s relatively easy to build a great PVR around an old motherboard, CPU and Windows 7, if you add high end TV tuners (encoders) and an average Graphics card (decoder) because all the heavy duty processing isn’t being done by the old hardware. It’s beeing done by dedicated high end video encoders in the TV tuner, or in the dedicated MPEG2 decoding pipeline of the Graphics card. Which rather bursts the balloon on the sense of acheivement to be honest. But for a machine which lives under the TV which is only used as a telly, does make a lot of sense.

But if you want a more versatile all round machine for which watching TV is only one of it’s role, then you just have to get something with a lot more CPU muscle, preferably with multiple cores so that it’s responsive. You then don’t need high end encoders and cheaper cards such as the Peak, will more thasn do the job. Stability might still be an issue though – as an asside, I notice that the machine is much less prone to crashing now. Fast Forward (when recording something else), was a bit risky previously. Makes sense really. Dedicated hardware encoders and decoders always do just that – encode/decode video. A CPU by contrast can be nagged by any one of a zillion different systems to interrupt what it’s doing and just quickly do something else. Which is all fine until it hits something that is time, or timing critical. Bang.

It still hasn’t cost that much. A new Black Gold Dual Tuner card is £80 which even when added to the cost of the new graphics – is under £100. Which is cheaper than buying a new motherboard, RAM, CPU – and you’d still have to buy the graphics card anyway. But it’s not the saving you’d hope for – particularly when you consider that you can buy good dedicated dual tuner PVR’s for less than double the price of the Black Gold card.

Can old Hardware run Windows 7 Media Center? 1

Posted on September 25, 2009 by danny

When the RC of Windows 7 came out – I was minded to investigate whether the same hardware I built to run MCE 2005 (ie: XP) could run Windows 7 Media Center (particularly as time goes by my MCE2005 system gets less and less stable) ? I never bothered to upgrade to Vista because it was clear that Vista was too processor hungry but with Windows 7 making waves for being as quick if not quicker than XP, I wanted to investigate.

The post for the original MCE2005 build is here

The original spec was:

  • Soltek 75DRV2 Motherboard (circa 2002)
  • AMD Athlon XP 1600+
  • 1.0 GB Ram (can run on 512MB – but gets sluggish once you have many recordings to index)
  • NVidia GeForce FX5200 Video card (fanless) with TV output
  • A Seagate Barracuda 7200 320GB hard drive
  • Twin Black Gold Signature TV cards to encode DVB-T (Freeview) signals
  • Gigabit LAN card

Well, in summary – yes it can – but there were a number of problems, mostly revolving around drivers.

After installing Windows 7 on a spare 80GB drive, audio and networking worked immediately. Also it can playback XVID natively so no XVID instal required. Nor does it require a third party mpeg decoder in the way that MCE2005 did. It has one built in, out of the box.

NVidia Graphics Card

The graphics card is old (though you can still buy it even new in 2009) – an NVidia GeForce FX 5200. The only drivers currently available were released back in 2006 (for Vista) and they do just about work. Worryingly NVidia have only so far released proper Windows 7 drivers for their more recent cards. I hope they expand support for older cards in due course but it doesn’t look promising.

Configuring the card was tricky, a lot of the NVidia Control Panel that had been available in XP was gone. I believe the Windows 7 driver model (inherited from Vista) has changed meaning those features would have to be reimplemented – if indeed it is even possibel to do so. Luckilly – I was able to select the correct resolution of 768 x 576 (PAL) once I had set “TV0” to be the main card output. The refresh rates available are way low (29Hz or something) – but I haven’t found away yet to tell Windows 7, that the display is a TV (a non plug-n-play device) and that it should be using 50Hz. That said it doesn’t seem to flicker – so it’s a low priority to fix.

Black Gold Digital Tuners

The Black Gold situation is annoying (and is well documented on “The Green Button” website here). Black Gold seem unable or unwilling to update the drivers such that two of these cards can work side by side in the same box. You can only use one. So one has to come out. Which means I shall have to buy another single or dual tuner card (from another manufacturer I think too). Not the best customer servicer.

Anyway, taking out one of the Black Gold cards got the other to work.

Performance

Initially, performance was pretty shabby. So I turned off a lot of unnecessary Windows 7 stuff to get some speed back. This page has some good information on this. More detail on the services can be found from Black Viper.

In essence I turned off a lot of services and switched off Aero (which although many people say this makes little difference – it’s a shite graphics card! – and Media Center doesn’t use Aero anyway).

In the process, I accidentally turned off the Human Interface Service which killed much of the Remote Control. So undid that. Also – it does need the Windows Search service.

Having done that – performance was much better and the media center UI is perfectly responsive.

Things get a bit more sticky once you start watching live telly – it does take a bit longer than MCE 2005 to get itself initialised and going – and is prone to the odd starting playback stutter – but once running it’s solid.

Similarly playing back pre-recorded video whilst recording another channel seems to work well without glitch in the recorded stream. Again playback startup is a bit slow.

Because of the problems with the Black Gold drivers – I was unable to test recording two streams simiultaneously whilst playing back a third.

The only significant lockup was when using the back button on live tv, it took me back to the guide (which is fine) but then got stuck taking me back to the main menu. Odd. Pressing the green button seems to fix this most of the time.

The one signifcant difference in hardware between the XP and Windows 7 setup’s was the Hard Drive – because I’m using my fast 320GB drive for my live MCE 2005 system, I had to use a slower 80GB Western Digital drive for the Windows 7 test.
This may well be significant and explain some of the stutters – I can’t prove that at the moment though. Certainly the faster drive can only improve things.
The Seagate manages 63.05 MB/s and has a 16MB cache whilst the Western Digital only manages 43.47 MB/s and has an 8MB cache.

Migration of Existing Recordings

Although Windows 7 MCE uses a new storage format for recorded TV, it seems to playback dvrms files transfered across from MCE 2005 just fine.

But then, there is XVID.

Oh dear. XVID.

I encode a lot of stuff to XVID. Movie’s and home Camcorder stuff. Playing any of this, even from the local hard drive was grindingly slow. Playback was quaerter speed, audio normal speed and the UI is completely unresponsive. Installing XVID in the hope that it would take over from Microsoft’s codec’s didn’t help either. Some other config required here perhaps. But I haven’t yet googled a way how (and I ain’t smart enough to work it out for myself!)

Again, looking at the Green Button website – this seems to be a common problem. Here’s hoping it gets sorted by the October release. Certainly decoding XVID’s usually doesn’t require much processing power at all – so it seems odd.

Then there is the aspect ratio of the XVID’s on screen – which displayed just fine in MCE 2005, but are completely wrong in Windows 7 being stretched height wise. Ugh.

Some further research shows that the XVID’s play fine in Media Player. Weird.

Conclusion

There is no doubt that at the moment the system does perform better where TV is concerned when running MCE 2005 – but the performance in Windows 7 is certainly not unuseable by a long shot.

And there’s a lot to like in the new UI with all the downloading of artwork for movies etc… plus the general reorganisation of the UI. It all seems to work well, logically and is responsive. Support for features such as fasr forward/revwind in XVID’s and other Video file types is much improved. And the extra digital buttons we get in the UK (“press the red button now for etc”) actually seem to work which they never did in MCE XP.

It would also have to be said that my MCE2005 install is no longer that stable and is likely to crash if left by itself for a week. It remains to be seen how stable Windows 7 MCE is by comparison.

So in short – when Windows 7 comes out for real – I’m definately going to try to move over to it with this hardware.

Even if XVID playback is screwed – someone will work out a fix for that!

Mind you, you’re never going to be watching HD on this system! 🙂

Building a Windows MediaCentre PVR from (some) reused parts 0

Posted on April 16, 2009 by danny

I’m a big fan of reusing old kit from the loft (ie tight fisted!) and we’d been wanting a PVR for quite a while. Windows Media Centre PVR’s are often specced to be high performance pieces of kit that can handle the latest games etc… However the actual TV part of the requirement needs next no grunt at all. The spec below is more than capable of recording 2 channels simultaneously whilst playing back a third pre-receorded show – and the heart of it, was recycled from the loft…

Reused bits:

  • Soltek 75DRV2 Motherboard (circa 2002)
  • AMD Athlon XP 1600+
  • 1.0 GB Ram (can run on 512MB – but gets sluggish once you have many recordings to index)
  • NVidia Gforce FX5200 Video card (fanless) with TV output (cost £20 when new).

Additional Hardware:

  • Big Slow Spinning fan to keep it cool quietly (cost about £15 if I remember correctly).
  • Similarly, quiet PSU bought (do you really want a noisy PC in your living room? Nah!)
  • A single Seagate Barracuda drive for storage (again quiet) £50
  • Twin Black Gold TV cards to encode DVB-T (Freeview) signals £50 each.
  • A Silver fronted DVD drive (£20).
  • A nice case. To make it a simple build, the normal PC case height. A Silverstone LC17 – this wasn’t that cheap (almost £100).
  • You will also need a Remote Control and an IR receiver for MCE. These can be found on ebay.
  • If you are going to want to store (or process) the recorded files on other machines, then buy a gigabit LAN card if you don’t have one (£10) so that you can move the files around quickly (they are huge!) – if you opt to do this over wireless you may contemplate suicide.

Software:

You will need a copy of Microsoft Media Centre for XP which you probably can’t buy new anymore. Its quite likely that the Vista version may not run on a machine this low spec as Vista is rather more hungry. But the XP version can be found easily on ebay. Would be interesting to see if the equivalent Windows 7 MCE is efficient enough to run on this when that comes out though…
Read the rest of this entry →



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