DirecTV2PC: Why such stiff PC requirements

[shaka999]

I'm curious, does anyone know why DTV2PC has such high performance requirements? I'm looking for a small low power laptop and want it to run DTV2PC. I know the netbooks are all too lame but a new batch of machines like the Acer 1410 can easily pull off 720p/1080i. Some 1080p content runs stutter free as well.

So, what is it about DTV2PC that makes takes so much more than this? Is the encryption really that power hungry?

[Stuart Sweet]

Basically it comes down to decoding MPEG4 HD content in real time while dealing with the copy protection. The HD stream is 8-10Mbps and that requires a lot from the processor and video card.

[LarryFlowers]

Stuart is correct, there is alot going on here and machines will have to have some guts to deal with it.

[shaka999]

Thanks for the quick reply.

I still don't quite get it. These cheaper PCs can easily handle 720p/1080i content. At least the ACER 1410 has MPEG4 acceleration.

[veryoldschool]

I'm curious, does anyone know why DTV2PC has such high performance requirements? I'm looking for a small low power laptop and want it to run DTV2PC. I know the netbooks are all too lame but a new batch of machines like the Acer 1410 can easily pull off 720p/1080i. Some 1080p content runs stutter free as well.

So, what is it about DTV2PC that makes takes so much more than this? Is the encryption really that power hungry?
I've been "playing with" DirecTV2PC on some fairly "lite" PCs.
MPEG-2 can be done with a fairly "lite" CPU. DirecTV does have more encoding than "regular" MPEG-2, but a 2.8 GHz single core Pentium seems to work.
MPEG-4 takes more power. This can be done with the newer video card/chips that support h.264. With one of these chips, I've been able to "underclock" my CPU down to 1.7 GHz [the slowest I can] and had "no problems" with MPEG-4.
"So" if you're looking for a "small low power laptop", make sure it has a good video chip. [basically from nVida or ATI]

[Stuart Sweet]

Thanks for the quick reply.

I still don't quite get it. These cheaper PCs can easily handle 720p/1080i content. At least the ACER 1410 has MPEG4 acceleration.

Not all 720p/1080i content is the same. I've seen internet content calling itself 1080p with a roughly 5Mbps bitrate. The same content on a Blu-ray disc would be 25Mbps and on DIRECTV probably 10-12Mbps. The resolution is actually less important than the bitrate.

[shaka999]

Thats pretty interesting info and gets me thinking.

The ACER 1410/1810T I was looking at uses

Intel SU3500 Core 2 Solo 1.4GHz

The passmark CPU charts seem to put this close to a 3GHZ P4 on the CPU charts. The GPU may be the sticking point but it does have Intel's 4500MHD which might be up to the task....

[veryoldschool]

Thats pretty interesting info and gets me thinking.

The ACER 1410/1810T I was looking at uses

Intel SU3500 Core 2 Solo 1.4GHz

The passmark CPU charts seem to put this close to a 3GHZ P4 on the CPU charts. The GPU may be the sticking point but it does have Intel's 4500MHD which might be up to the task....
From a "quick google" the GPU looks to support h.264 & HDMI [HDCP].
This just "might" work for DirecTV2PC.

[Stuart Sweet]

Having had an actual 3GHz P4 I would not pin your hopes on this machine being able to run DIRECTV2PC happily.

[veryoldschool]

Having had an actual 3GHz P4 I would not pin your hopes on this machine being able to run DIRECTV2PC happily.
"me too" and with the first release of DirecTV2PC, I "only" had problems with MPEG-4 [1080i, as 720p worked].
With the newer release that uses the GPU for h.264, the CPU loading is greatly reduced, leaving only the MPEG-2 HD requiring CPU "horsepower".
[again] with my Pentium 4 HT, clocked @ 1.7 GHz, MPEG-4 only used 50% CPU with my ATI [AGP] 3650 video card. At 2.8 GHz CPU, MPEG-2 started to show problems.

[shaka999]

Having had an actual 3GHz P4 I would not pin your hopes on this machine being able to run DIRECTV2PC happily.

Thanks for the warning Stuart. Just playing around with options. You could put together a pretty cheap laptop that would run DTV2PC just fine but these thin and light models are compelling.

[veryoldschool]

Thanks for the warning Stuart. Just playing around with options. You could put together a pretty cheap laptop that would run DTV2PC just fine but these thin and light models are compelling.
"I guess" it should be stated that trying this has risk, since it's running near the minimum required.
If you do try it, I'd be interested in whether it does work, or what it can and can't do.
I've been pushing the limits of the minimum hardware needed from the very beginning of testing DirecTV2PC. Most of this time the Advisor has told me it won't work, yet I've been able to find what does and doesn't, then tweaked my system to "just get by".

[shaka999]

VOS,

What OS have you been testing with? When your right on the edge it might make a difference. The ACER comes with Vista but is upgradeable to Win 7 in the future. Vista is such a hog ....

[veryoldschool]

VOS,

What OS have you been testing with? When your right on the edge it might make a difference. The ACER comes with Vista but is upgradeable to Win 7 in the future. Vista is such a hog ....
XP & Vista.
With XP 1 gig of memory worked fine, but Vista needs 2 gigs.
Once there is enough memory, they both seem to work fine. I'm using 5+ year old hardware, so [after fighting with Vista drivers] I haven't tried Win7.

If you can get your hands on what you're thinking about and it's running Vista, there is a "Windows experience index" that might give you an idea of what the CPU & video is "rated at".
This CPU is 4.3 & the video is 5.4 [gaming is only 5.2]

[hdtvfan0001]

Running XP SP3 here....but in my case...the video card lacked the horsepower.

Since it was dated anyway, and I planned to upgrade it anyway in anticipation of WIN7, I got a fine new ATI Ratheon 3600 series video card with 512MB onboard ram for under $90, and everything, including Direct2PC works.

[The Merg]

I'm currently running on a P4-2.8Ghz with 2.5GB RAM and my video card is a NVIDIA GeForce 7800GS with 256MB RAM. It plays back MPEG2 recording mostly without issue, but every now and then I do get some stuttering. I don't have HD service, but I would anticipate that I would have some issues with MPEG4 considering it just manages to play back MPEG2 recordings.

- Merg

[veryoldschool]

I'm currently running on a P4-2.8Ghz with 2.5GB RAM and my video card is a NVIDIA GeForce 7800GS with 256MB RAM. It plays back MPEG2 recording mostly without issue, but every now and then I do get some stuttering. I don't have HD service, but I would anticipate that I would have some issues with MPEG4 considering it just manages to play back MPEG2 recordings.

- Merg
If your 7800GS can support the h.264 decoding, then you would be fine.
Your 2.8 GHz, is right at the speed MPEG-2 [which is all CPU decoding] starts to have problems.

Now I also have a PC with the nVidia 6600 cards(s) and that one needs every bit of the (3 GHz) PentiumD for MPEG-4

You should be able to "test it" with a HD VOD.