I've been a regular user of HDMI on my PC's for HTPC use for some time, and theres a lot of little oddities and quirks that arent easily searchable online. Figured what the hell, lets make a community guide to help beginners set it all up So without much ado, here be some advisories. Start by reading this link for details on the various versions of HDMI http://www.audioholics.com/hdtv-formats/understanding-difference-hdmi-versions The technology: HDMI as a standard, is basically DVI + audio, with a few limitations. 1. The video resolution can limited compared to dual link DVI, many devices limited to 1920x1080 60Hz (aka 1080p) 2. The Audio is often limited to stereo, unless its a pre-encoded dolby digital or DTS source (DVD/BD). This can be bypassed with a high end receiver that supports uncompressed LPCM audio. 2a. 99% of the time, if you use an audio output from your HDTV, you'll be stuck with stereo only. Receiver has to be before the TV for 5.1/7.1 sound. I've got three HDTV's with SPDIF output and you only get 5.1 from TV tuner sources - HDMI needs a seperate receiver. Might as well mention MHL (the mobile phone/tablet standard, micro USB to HDMI) Spoiler This ones pretty simple, as at present there is only two standards, 1.0 and 2.0 1.0 can only do 720p, 1080i (30Hz interlaced) or 1080p/24 (24Hz/FPS) - on a 1080p HDTV, it often prefers 1080p/24, which looks stuttery and garbage. using an MHL 2.0 cable will fix that issue. a TV with built in MHL 2.0 will charge the device from the TV, most adaptors have external power input so they charge anyway. If you have a 16:10 tablet and not 16:9, you're screwed for HDMI output except with the stock media player - everything will output a 16:10 signal squished to 16:9, so expect blur and black bars. stock media player can fix it on samsungs, but in general its a flaw of android tablets. Quirks: 1. HDMI has no 'standby' function, so telling windows to turn screen off after X minutes just results in a black screen No fix to this one, unless your TV has a motion sensor like mine does to turn itself off. 2. When you turn your TV on/off or change channel, the image flickers and windows get resized, possibly crashing programs. This one is a pest with a few solutions, each with their own flaws. Whats happening is that modern HDTV's can tell devices the TV is off, so that a bluray player or game console can power down to an idle state. Unfortunately to a PC, this means windows thinks the HDMI cable was disconnected, and tries to look for another monitor that may not exist, so it drops to 1280x1024 while it scans for a monitor to be detected. Spoiler Solution A: Connect a secondary monitor over DVI or VGA, at the same resolution and tell windows to duplicate the screens. This is the cheap option as TV's have a second connection and you're likely to have a spare cable. The downside is that many gaming level graphics cards up their idle clocks in dual monitor, which can kick up the power consumption and heat of your PC. Solution B: If you get a HDMI switch/splitter or audio receiver, the PC will detect that and maintain the connection. The downside is that a cheap splitter may not work (one of mine only works with 8 bit colour when i have 12 bit deep colour HDMI), and that it of course, costs money. This was my solution, and it works well for me. (not the unit i have) 3. the image is too large or too small for the screen Spoiler Multiple causes and solutions here. if you have an AMD graphics card, there is a slider in the catalyst control center that may help Otherwise the problem can be caused by overscan settings on your HDTV, incorrect resolution (not all TV's are 720p or 1080p, I personally own a 1366x768 HDTV and have seen a 19" 1440x900 HDTV) Try every HDMI port as well, as some TV's (my 768p samsung for example) only work properly on one HDMI port. On my samsung, HDMI2 is 768p, while HDMI 1 and HDMI 3 only support 720p and 1080i - fine for game consoles, terrible for PC. The above two problems are caused by dodgy TV makers doing something annoying - HDMI standards require a 720p input as a minimum with 1080i/1080p added on top, but they dont require the *panel* to actually be that resolution. Cheap HDTV's use a cheap panel, and shrink or stretch to fit at an obvious image quality loss to a PC/HTPC user. 4. Image quality varies/solid black images have a weird pattern This ones common on HDTV's, and is quite simple to fix: turn off all the fancy settings in your TV. Name the connection to "PC" set it to "Game mode" if it supports it, and disable all edge enhancement and 'quality improvement' options. They're there to cover up crappy television feeds, but ruin a high quality HDMI signal.