The best job for a spare TV is not a second place to watch Netflix. It is a screen you glance at, running quietly in a home office, kitchen, garage or basement while you do something else. Ours shows the stock market, which is a biased answer from a team that builds a stock market app for TV. But the old TV has to work first, and most spare TV questions are about cables, power, mounting, burn-in and the electric bill. So we start there.
We test MarketCast on a shelf of Fire TV sticks, Google TV boxes and Apple TVs plugged into whatever TVs we have lying around. What follows is what we have learned leaving screens on all day, plus a few facts we checked.
Will my old TV work with a streaming stick?
If it has an HDMI port, almost certainly yes. A 4K stick works fine on a 1080p or even a 720p TV; it simply sends the resolution the TV asks for. For a glance screen the extra pixels do not matter anyway.
If it has only the red, white and yellow jacks, you would need an HDMI to AV converter, and small text comes out too soft to read. That TV has earned its trip to the recycler.
If it is an old smart TV, ignore its built-in apps. Their app stores stop getting updates long before the panel wears out, and a stick in the HDMI port gives the old panel a current, supported platform.
Setting up a spare TV in a home office, kitchen or garage
Home office. Put the TV slightly off to one side, where you can see it without turning your head from your monitor. A 32 to 43 inch screen across a small room is plenty for prices and headlines.
Kitchen. Keep it away from the steam and grease above the stove. A wall near the table beats the spot over the range.
Garage or workshop. Check the temperature range in your TV's manual. Samsung, for example, lists an operating range of 50 to 104 degrees Fahrenheit for its TVs, and a wider range for storage while switched off. In an unheated garage in January, let a cold TV warm up before you turn it on.
Basement or man cave. The usual problem is Wi-Fi. If the stick buffers, a box with an Ethernet port (the Google TV Streamer or the onn 4K Pro) on a cable fixes it for good.
Mounting. The four threaded holes on the back of the TV are its VESA pattern, in millimeters (100 x 100, 200 x 200 and so on); any mount rated for that pattern and the TV's weight fits. Screw it into studs, not just drywall. On the wall, a stick plugged straight into the TV sits behind a slab of metal, which hurts Wi-Fi. The short HDMI extender cable that comes in the box with the Fire TV Stick 4K Max moves it a few inches away and usually helps.
Can I power a Fire TV Stick from the TV's USB port?
Sometimes, but we would not. Many TV USB ports do not supply enough current, and the stick will show a low power warning; Amazon's advice for that warning is a wall adapter. On many TVs the USB port also shuts off with the TV, so the stick cold boots every time you turn the screen on. Plug the stick's own adapter into the wall or a power strip behind the TV.
Will a TV left on all day get burn-in?
It depends on the panel. Most spare TVs are LCD (sold as LED, which refers to the backlight), and RTINGS, which runs long-term burn-in tests, found LED TVs immune to permanent burn-in. An LCD can show a faint after-image after hours of the same static picture, but it fades once the picture changes.
OLED is different. Its pixels wear unevenly when the same bright logo sits in one place for hours, and that wear is permanent. Old plasmas share the weakness. On an OLED, lower the brightness, leave pixel shift and panel refresh on, and show content that moves.
How much electricity does a TV use left on all day?
Less than most people guess. The Energy Star listings we looked up for certified 49 and 50 inch LED TVs show them drawing around 70 watts while on. Run one like that 8 hours a day on about 250 weekdays a year and it uses roughly 140 kWh. At the U.S. average residential price the Energy Information Administration projects for 2026, about 18.2 cents per kWh, that is around $25 a year. Leave the same TV on around the clock and it is closer to $110.
Older sets, especially early LCDs and plasmas, can draw a good deal more, and local rates vary. A plug-in power meter gives you the real number in a minute.
How to make a spare TV turn on and stay on
HDMI-CEC. This lets the stick turn the TV on and switch it to the right input. Every brand names it differently: Anynet+ on Samsung, SimpLink on LG, BRAVIA Sync (Control for HDMI) on Sony. On a Fire TV it is under Settings > Display & Sounds > HDMI CEC Device Control. Turn it on at both ends.
The TV's own auto power off. This is the one that catches people. Many TVs switch themselves off after a few hours without a button press on their remote, even while a picture is playing. Samsung calls it Auto Power Off under General > Eco Solution, and LG has a similar timer in its general settings. If your market screen goes dark every afternoon around the same time, this is why. Turn it off, or set it to the longest option your TV allows.
The stick's screensaver is less of a worry: an app built to stay on screen, like ours, keeps the display awake while it is open.
What to put on a spare TV: a market screen
A glance screen should show something that changes during the day, that you care about, and that you can read across the room with the sound off. A news channel is built for listening. A photo slideshow never changes. The stock market passes all three tests.
That is what we built the Stream in MarketCast for. It puts your stocks, the major indexes, the day's movers and the headlines full screen on your TV, scene after scene, with a ticker tape along the bottom. You add your stocks by scanning a QR code with your phone, and after that you never touch the remote. It is free, with delayed prices, supported by commercials and sponsors. Premium is our real-time data package: real-time stock prices, crypto around the clock, no commercials, Congress trades and customization.
Because the scenes keep changing, it is also gentler on a panel than one static table all day. If the spare TV is going into an actual office for a team rather than your home, we have a guide to a stock ticker display for an office or lobby, and our Enterprise plan, in early access, runs every TV in a firm from one desktop dashboard.
Which streaming stick to buy for an old TV
For a screen that runs all day, the number that matters is memory, not the 4K on the box. In our testing, even the 2018 Fire TV Stick 4K, with 1.5 GB, can run out of memory with a market screen left on overnight; we had to shrink our image caches for it. Aim for 2 GB or more. Our picks, all of which run MarketCast natively:
- Fire TV Stick 4K Max (2nd gen). The Fire TV stick to buy, with 2 GB of memory. If you have a 2023 Fire TV Stick 4K (2nd gen) in a drawer, it has 2 GB too and is a fine choice for this.
- Walmart onn 4K or onn 4K Pro. Full Google TV for very little money. The Pro adds more memory and an Ethernet port.
- Google TV Streamer. Fast, with Ethernet built in. Our pick for the basement.
- Fire TV Cube. Amazon's fastest Fire TV, and the one we would put in a home office that shows the market all day.
- Nvidia Shield. Still quick, if you already own one.
- Apple TV 4K. The smoothest platform we build for. More than a spare TV needs, but if the rest of your house is Apple, it is the nicest of the lot.
One warning about Amazon's newest sticks. The Fire TV Stick 4K Select and the 3rd gen Fire TV Stick 4K that Amazon announced this fall run Vega OS, Amazon's new Linux-based system, not Android. Android apps do not install on them and there is no sideloading. MarketCast works on both, so any current Fire TV stick will turn that old TV into a market screen. We explain the whole change in what Vega OS means for your Fire TV apps.
If the spare TV is a Roku TV, MarketCast is not on Roku (here is why), but any device above plugs into a free HDMI port. For speed comparisons, see the fastest streaming device we test on.
Put the old TV back to work
Once the stick is in, the screen is on the wall and the auto power off is out of the way, download MarketCast for free on Fire TV, Google TV, Android TV or Apple TV, add a few stocks from your phone and start the Stream. Our home office stock ticker guide covers desk setups, the setup guide covers each device, and if you are weighing a TV against a scrolling sign, read LED stock ticker vs a TV. The old TV in the garage was going to sit there either way. It may as well tell you how the S&P 500 is doing.