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Comment by baddox | Hacker News Reader

Is his final point (about overscan) still relevant? Years ago I used to hear HDTV enthusiasts urging everyone to check their TV settings, but in the last 2-3 years, I've only dealt with PCs hooked up to a few HDTVs (all with 1080p native resolution), and I haven't seen a single one that overscans a 1080p DVI or HDMI signal by default. The author acts like it's a certainty that your 1080p TV will by default overscan a 1080p signal.

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It's not unusual for DVI input to be underscanned by default, but the HDMI spec says that 1080p should be overscanned. Disabling that requires your TV to advertise its feature set correctly (there must be a VCDB in the EDID, and it has to indicate that it supports underscanning of CE video modes) and your output device needs to send a type 2 infoframe with a request that the mode be underscanned. I really don't know how common it is for all of this to work without manual intervention - most of what I end up playing with is whatever's sitting in hotel rooms, and that's not necessarily a good representation of the current market.

Awesome to see you answering questions here. Let me state that your posts on pgo are better than anything tdwtf can deliver any day. Thanks a lot for looking into these pits (ACPI..?) so that I can be blissfully ignorant. I owe you gin.

Two data points:

My four-year-old Samsung has a "Just Scan" mode that maps 1:1 to the panel's pixels. I've never had a problem with overscan over HDMI, DVI, or VGA.

When I was home over the holidays, I noticed that even my parents' Black Friday mystery-name TV from Menards offered a 1:1 pixel mode. This mode was strict enough to map a 480i picture into a little box in the middle of the screen.

+1 look for "Just Scan" as a display mode on your TV. On my LG and many Samsungs this does a 1:1 pixel mapping from your source input.

I have a one-year-old Samsung LED-backlit LCD and it overscans from a unibody Mac Mini via HDMI into the TV's PC-specific HDMI port. I have to fix it manually with the overscan slider in OSX's display preference pane.

I also have a one-year-old Samsung and I managed to get it to not overscan for at least one input. Put your Mac Minis HDMI into the HDMI 1 / DVI input and then select the input in the Source menu on the TV, press Tools on the remote, and chose PC as the name of the input. This magically turns off overscan. Hope it works!

Did that already; no joy. It's not a problem because of the overscan slider in OSX, but it was a huge annoyance before I upgraded the mini (you need the built-in HDMI to get the overscan adjustment).

Unfortunately you're most likely losing resolution in this case. If, for example, your TV is cutting off 3% of the image, then the video card is scaling your whole desktop down from 1920x1080 to ~1862x1048, which will result in more than 3% apparent resolution lost due to less-than-optimal interpolation.

I'm fine with that; the Mini is used as an HTPC, so I really need the overscan correction only so I can see the menus in VLC / Quicktime.

You should probably have a look for a way to disable overscan in your television's manual. My several year old Samsung DLP supports "PC mode", which disables overscan.

Yeah, same with our LG LED-LCD. It may have been possible to disable it in some menu, I can't quite remember now.

I have a Panasonic VT30 plasma display that was released May 2011 and I had to explicitly disable overscan when I plugged in my PC via HDMI.

I have a LED 6400 Samsung SmartTV and as I plugged my PC on the HDMI (did no try DVI yet) I simply selected the Automatic video mode and no edges are cut.

I have a 6-month old 1080p TV that apparently has no way to disable overscan.

Poor purchasing decision I'll grant (though it is a decent TV), but my point is this area can still be a minefield.

Every single TV I've got right now does overscan (two HDTVs) only one gives the option to disable it. I've even got a computer monitor that has only HDMI connectors and overscans by default.

It seems that it's a wash as to whether you will hit this or not all depending on the brand.

While most newer TVs are smarter about overscanning signals from a PC, the issue has gone the other way - to compensate for TVs which overscan, AMD's Catalyst/Vision drivers automatically underscan their output when attached to an HDTV.

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