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Polaris573
11-17-2006, 04:43 PM
A friend of mine tried to put an HTPC together. He has and HDCP compliant TV but the video card is a 7600GTX and doesn't support HDCP, therefore we can't connect it using DVI and have to to use analog component. For some reason we still can't run the TV at any of the correct resolutions via the analog connection. We did manage to find an odd resolution that kind of worked and attempted to play a movie, in which case we got some DRM message about not being allowed to display movies via an analog display. I really don't know much about HDTV, HDCP and all the other related things. Any information would be greatly appreciated.

Bill_Bright
11-18-2006, 04:39 PM
video card is a 7600GTX and doesn't support HDCP, therefore we can't connect it using DVI and have to to use analog componentThat is not how it works. You are confusing a physical connection, DVI, with a form of digital rights management (code used to prevent illegal copying), HDCP. DVI is just a type of digital interface. Having (or not having) DVI connectors on the monitor and/or card has nothing to do with HDCP, only whether the video signal from the card to the monitor is digital or not. HDCP is a digital format and so if HDCP is supported, there must be a digital connection. It can be through a DVI connection, or it can be through an HDMI (which also carries the audio).

DVI does not automatically mean High Definition - it just means there is a digital interface.

In order to watch HD video, you need a HDCP ready TV (any TV with the "HD Ready" logo should be HDCP capable) and a HDCP capable playback device, such as a blue ray or HD-DVD player, or HDCP ready graphics card. So, if your card does not support HDCP, you need a card that does.

See HDMI, DVI, and HDCP (http://tv.about.com/od/hdtv/a/hdmidvihdcp.htm).

Polaris573
11-18-2006, 04:49 PM
Right I think that's what I said. The video card doesn't support HDCP while the TV does so connecting to the DVI port on the TV will not work. Or am I still confused? He was trying some workaround using a converter to change to component he was under the impression that he could get an HD picture this way. I must confess I didn't see it that closely. Is there any way at all that we can get an HD picture on the HDCP enabled TV without an HDCP video card? That's what I really need to know I suppose.

Bill_Bright
11-18-2006, 05:27 PM
That's not what you said. You said, the card does not support HDCP, therefore you had to go analog. That is not a given. The lack of HDCP only means you can not play HDCP content. If both monitor and card support DVI by physically having the DVI connectors, then you can, and should for best quality, establish a fully digital connection between the card and monitor. The vast majority of cards do not support HDCP, but most now days do support a digital interface, DVI. In fact, many cards today only use DVI connectors and if you have a CRT monitor, or an LCD without DVI (many, if not most budget LCDs only use the standard (and old) D-Sub 15-pin VGA connectors), you have to use one of these:
4546

Remember, DVI does automatically mean HiDef.

Think of HDCP as a format or protocol, and DVI (or HDMI or even D-Theater D-VHS tape) as the hardware interface needed to view HDCP content.

Polaris573
11-18-2006, 05:35 PM
Okay. I understand now. I'll tell him to try the DVI connection. He still won't be able to play his blue-ray or HD-DVD movies on the thing though correct? Which I think is the reason he was trying to find a workaround in the first place.

Bill_Bright
11-18-2006, 05:39 PM
Is there any way at all that we can get an HD picture on the HDCP enabled TV without an HDCP video card?No. :( You need some HD capable device to send HD to the TV.

Bill_Bright
11-18-2006, 05:42 PM
Okay. I understand now. I'll tell him to try the DVI connection. He still won't be able to play his blue-ray or HD-DVD movies on the thing though correct? Which I think is the reason he was trying to find a workaround in the first place.He may be able to play them, but not at HD resolutions.

Darren
11-20-2006, 09:39 AM
To my knowledge HD quality is just a certain resolution, 1280x720 for smaller monitors/tvs or 1920 × 1080 pixels for larger monitors/tvs.

So if your friends tv/monitor can support one of these resolutions while using a DVI-input in theory it should be HD quality.

However to get full sensation the media (DVD) needs to be HD compatible as well, and the truth of the matter is most DVDs are not yet recorded in a HD complient manner yet.

PS. (movies can be downloaded in HD quality if yor into the torrent scene)

Bill_Bright
11-20-2006, 03:00 PM
To my knowledge HD quality is just a certain resolutionNot exactly. HD DVD (either blue-ray or HD-DVD) use a much shorter wavelength signal to burn (and read) the pits and valleys (highs and lows - 1s and 0s) into the media. Since physics says that T = 1/F (Time = 1/Frequency) and we know time is a constant (1 second = 1 second), if the wavelength (the physical length of one cycle) is shorter, that means you can jam more cycles in the space consumed during 1 second in time (as determined by the rotation of the disk and other factors). In other words, the shorter the wavelength, the higher the frequency. The higher the frequency, the more information is contained in each second or play.

In terms of video, if you have more information available in each second, you can draw more horizontal lines of resolution (if the HW is able) - and the more lines drawn per second is what determines the picture resolution. Standard TV in the US, NTSC, is capable of 525 lines. However, the signals transmitted, over the air or through cable, only draw about 250 lines at about 30 FPS. Standard DVD uses 480 lines which is why DVD looks better than broadcast or cable TV.

HDTV, on the other hand, is up to 1080 lines and that is possible because of the "density" of the data stored on the disk - shorter wavelength means greater density - but also means you must have a player capable of reading the shorter wavelengths, and you must have a display with electronics fast enough to process and display that many lines.

So, if your standard DVD player is not capable of reading the shorter wavelength - it might as well be a blank disk and your HDTV will be showing a polar bear eating marshmallows during a snowstorm.

if your friends tv/monitor can support one of these resolutions while using a DVI-input in theory it should be HD qualitySorry, this is not correct either.

HD does not equal digital. DVI is just a physical interface - a connector for "digital" signals. A digital signal may or may not be HD - just as a DVD may or may not be HD - that depends on the original content and how it was created and the media in which it is stored. For example, the vast majority of video cards and virtually all but budget LCD monitors support a digital interface - DVI. But only a very small handful of cards support HD.

Don't confuse digital with analog, or digital with high definition. Technically speaking, you can certainly have analog HD - but since the RF bandwidth and storage requirements for analog signals are HUGE, digital is used, with the added advantage of less noise, less distortion, and easier delivery.

Clear as mud, right?

lemonadesoda
11-20-2006, 03:18 PM
@Polaris573

Unfortunately, the whole format/hardware issue is a mess. Why? Because hardware either misses critical components of the "protection" methods, or, the hardware has consumer-friendly, PC-unfriendly protocol restrictions.

I have a fabulous SHARP HDTV that has a rubbish "sharpening" algorithm that totally ruins some types of input, e.g. my daughters cartoons. Can you turn it off? Nope.

In your situation, you probably have a "clever" TV that is limiting what you are able to play through it, dispite the fact that it COULD, its firmware WONT let you.

To make the digital input work from the PC (after you find the right cables), or to give you the ability to try different resolutions on the analog input, you need to try some software utility that will allow you to use resolutions that the monitor profile does not normally let you use.

Good luck!

W1zzard
11-20-2006, 03:22 PM
which tv model is that? some tvs will not accept hd signals without hdcp at all, via any link. most newer ones take any resolution without hdcp.

i am using a dvi to hdmi converter cable (get the cheapest one) on my plasma. no need for hdcp

Darren
11-20-2006, 04:20 PM
Think our techno talk scared Polaris573 off!!, dont be scared to reply Polaris573, these people want to help you!

Polaris573
11-20-2006, 04:21 PM
It's an RCA. I'm not sure what model. I'll have to get back with you on that.

Think our techno talk scared Polaris573 off!!, dont be scared to reply Polaris573, these people want to help you!

I'm a moderator, I'm here all the time. All of these new posts happened while I was asleep or in class. :laugh:

W1zzard
11-20-2006, 04:22 PM
RCA? i mean manufacturer + model .. not the available inputs .. and rca sucks by the way

Polaris573
11-20-2006, 04:24 PM
RCA is a manufacturer. http://home.rca.com/en-US/rcahome.html

Bill_Bright
11-20-2006, 06:55 PM
tvs will not accept hd signals without hdcpLet's not get confused here. TVs don't care about "copy or content protection" - the Motion Picture Association of America (MPAA) does however, and so HDCP (High-Bandwidth Digital Content Protection) (not copy protection) was developed (by Intel) to eliminate the reproduction of copyrighted material, while still allowing you to make a copy, time shift, etc.

In the future IF the MPAA gets their way and all broadcasted HD content becomes HDCP enabled (approved by the FCC in '04, but halted by and still in the courts) THEN you will need HDCP capable equipment to process the encryption/decryption process via the HDCP "broadcast flag". For those currently with HD-"Ready" sets receiving HD through a converter box may need a HDCP box. Those with an HD-able TV already, then you may or may not have to get some sort of table top box to view HD content - plain old digital will be no problem.

The main thing is, HDCP is a legal issue (dare I say "political" issue?) about content protection and not about the technical abilities or limitations of audio/video reproduction hardware.

Much of the confusion, I think, comes from the fact that HDCP depends on digital technology and the exchange of digital information between devices. There are only two digital formats widely used (not counting fiber) DVI and HDMI. Some DVI connectors have HDCP aware intelligence behind them, others do not. Most but not all TVs with DVI do support HDCP. But, HDCP is an integral part of the HDMI standards, which are rapidly taking over as the standard - DVI is going away eventually because it is inefficient - a DVI connector is big and carries only the video - HDMI is smaller and carries HD video and up to 8 discreet HD audio channels.

My advice for Home Theater equipment is don't buy it unless it supports HDMI. For HTPCs, well, DVI will do, but keep an eye out for more and more HDMI video cards.

Polaris573
11-21-2006, 05:06 PM
Ah well. He's decided to give up. He's going to rebuild with an HDCP compliant video card at some point in the future. Thanks for your help everyone.

Bill_Bright
11-21-2006, 07:10 PM
Ah well. He's decided to give up. He's going to rebuild with an HDCP compliant video card at some point in the future. Thanks for your help everyone.Of course that's always the problem - the technology that is just a little bit better is always just around the corner. There's a conspiracy going on that holds up that technology until the day after I bring home what was the best option. :banghead: The only solution is to buy it, then immediately and thoroughly isolate yourself in a cave, void of all technology news.

Polaris573
11-21-2006, 07:38 PM
Of course that's always the problem - the technology that is just a little bit better is always just around the corner. There's a conspiracy going on that holds up that technology until the day after I bring home what was the best option. :banghead: The only solution is to buy it, then immediately and thoroughly isolate yourself in a cave, void of all technology news.

He built the HTPC specifically to playback HD-DVD and Blue-Ray movies in High definition. If you can provide a solution that will allow him to do that without buying a HDCP compliant video card then by all means do so.

Bill_Bright
11-21-2006, 08:14 PM
I wish it were that easy. Just the fact the industry has not settled on a HD standard and you have to accommodate both HD-DVD and Blue-Ray illustrates the problem - for both HTPC users, and traditional HT owners. For me, I have not yet adapted either HD solution - and rent an HD DVR from my cable provider - though I am not happy with that solution either. Nor was I happy with any of the HTPCs I have built over the last couple years - fortunately, my clients were. I built one for me about 2 years ago, but pulled it out of my HT because I could hear the fans, even though I had top-end Papst and speed controls on the case and a nice Zalman on the CPU.

And so I wait until a rock solid HD with HDCP video card comes out that supports passive (no fans) cooling. It does not help that there have been "issues" with HDMI not working properly in terms of providing optimized video in multi-source applications - DVR, DVD, HD Cable, or HD antenna - to the point where some in the audiophile world recommend staying with the same maker for your amp/receiver, optical player, and monitor/TV, when possible, much as many recommend WiFi networks consist of access points and adapter cards from the same maker too - especially if attempting to use the new "draft" 802.11n standard.

I just came across this recent AnandTech HDCP Graphics Card Roundup (http://www.anandtech.com/video/showdoc.aspx?i=2874&p=1) that makes for some good reading. It has convinced me to wait until spring at least before I consider building my next HTPC with HDCP. Maybe by then we will know more if the world will settle on the HD-DVD or Blue-Ray as DVD's HD standard. If so, let's hope Beta wins and VHS goes by the wayside!