In the old days, getting your PC game on away from your desktop was easier said than done, limited to laptops that were portable in name only: thick, hulking behemoths stuffed with discrete graphics processors and large cooling components to match. Sure, you might coax World of WarCraft or some indie titles into running on CPU-integrated graphics, but most modern 3D games? Fuhgeddaboutit.

That was then. This is now, and now, the new in-home streaming feature Valve recently introduced in its blockbuster Steam gaming platform can turn any laptop into a full-fledged gaming machine--even older notebooks with ho-hum power, or Linux or OS X machines or Windows 8 tablets. It's all done by streaming games from your primary gaming PC to any computer in your house in OnLive-like fashion, but Steam's in-home streaming only works on your home network--and it's dead simple to set up.

Here's how to start playing all sorts of modern games--WolfensteinWatch Dogs? Transistor? Why not!--on your clunker of a computer.

The basics

Steam's game streaming isn't magic and it isn't powered by remote servers, so as I said, you'll need an active gaming PC to use as the brains of the operation. The game itself actually plays on your "host" PC, but Steam encodes and sends an audiovisual stream of the action to your secondary "client" laptop (or SteamOS machine, or whatever), while simultaneously sending your controller or keyboard and mouse commands from your secondary laptop back to your primary PC.

As with all PC gaming experiences, the graphical firepower of your host rig directly impacts the end results. If your gaming PC has a low-end graphics card, it'll only be able to send low-end visuals to your client laptop. (Obviously.)

At a minimum, Valve says you'll need a quad-core processor in the host machine, the faster the better--between encoding the video and, you know, actually playing the game, streaming hits your processor hard. You're probably going to want a discrete graphics card in your host rig, too, since the point of this exercise is to provide a better gaming experience than integrated graphics alone can provide. The host machine has to run Windows 8, 7, or Vista, as well. (Sorry, Windows XP holdouts.)

The requirements for client PCs are much less strict: The only thing you need is a PC with support for hardware-accelerated H264 decoding. The vast majority of PCs released in recent years can handle streaming, no problem--our hands-on with the Steam in-home streaming beta was partially conducted on a 2006-era MacBook, for instance.

Beyond the PCs themselves, the quality of your in-home network makes a big difference to Steam in-home streaming. For best results, everything should use a hardwired connection, but that's not always feasible.

Hayden Dingman's hands-on with the beta version was conducted on an older 802.11g network. While he was able to play slower games and even Just Cause 2 with minimal latency, he had a less pleasant experience with faster-paced games. Twitchier games like The Witcher 2: Assassin of Kings and Bioshock Infinite stream fine enough on my 802.11n network with some basic tinkering, however. (More on that later.) Using the 5GHz band or an 802.11ac router would theoretically deliver even better results, and comments in this forum discussion largely back up that theory.

Using Steam in-home streaming

With that out of the way, now onto the (mostly) easy part: Actually playing games with Steam in-home streaming.

Keep reading to learn how to stream Steam!

The process couldn't be easier. Simply make sure both computers are turned on, connected to the same local network, and logged into the same Steam account. If all that's set, a pop-up will appear in the lower-right corner of your screen, letting you know you're connected to your primary machine.

Your Steam library will be shared between the two PCs, and a Stream option will appear for games that are installed remotely. (You'll need to install the games you want to stream on your host PC first, of course.) If any of your games are installed on both machines, you'll be able to choose whether you want to stream it or play it straight from the PC you're holding.

That's it!

If you want to try to play a game that isn't offered on Steam, try adding it via the Games > Add a Non-Steam Game to my Library option on your host machine to try and force the matter. Valve's streaming FAQ says that might work, but warns that streaming non-Steam games is not officially supported.

Trouble-shooting Steam in-home streaming

Troubleshooting streaming problems is also fairly straightforward, assuming your hardware and home network are up to snuff to begin with.

If your games are doing the jitter-bug--in-home streaming handles latency by dropping the frame rate, rather than dropping the picture quality, for some bizarre reason--open Steam on your client PC and head to Steam > Settings > In-Home Streaming in the menu bar. Under the "Client options" portion, you'll see options for Fast, Balanced, and Beautiful, with Balanced enabled by default. Try dropping the setting to Fast.

If that doesn't do enough, click Advanced Client Options, then open the Limit Resolution To drop-down menu and select a less pixel-packed streaming resolution option. With my setup--a hardwired Core i5 desktop PC streaming to various laptops over 802.11n--dropping the resolution to 720p helps even action-packed games stream with few hitches. (The frame rate can still get a little hairy in particularly explosive and fast-paced scenes, though.) My Wi-Fi doesn't have to struggle for airspace with competing networks in my rural abode, however.

What, that didn't fix the problem either? First, make sure the Enable hardware encoding and Enable hardware decoding options are, in fact, enabled on your host and client machine, respectively--they should be by default. You can also try enabling the Prioritize network traffic option on your host machine, or switching your router to the less-trafficked 5GHz spectrum band (if your router supports the 5GHz band). If that doesn't work, it's time to break out the Ethernet cables. There's a reason Valve recommends using wired connections--they're stronger than wireless ones.

Wrapping up

That should be about it. While Steam's in-home streaming has officially dumped its beta tag, don't be surprised if you run into occasional frame rate or input woes, as the technology is still in its early days. Some games might not play audio, or they might refuse to launch whatsoever. More frantic games may have hiccups. Again, Hayden Dingman's hands-on with Steam in-home streaming can give you a good overview of what to expect.

All that said, it's held up remarkably well for me thus far. Sure, the introduction of Steam in-home streaming is meant to pave the way for living room-ready Steam Machines and make Steam for Linux's paltry (but growing) library less painful, but it's great being able to game on your laptop while you're lounging on the couch or lying in bed. Merely plugging an HDMI cord into your laptop can bring your entire Steam library to your TV, and in-home streaming also brings the full Windows-based Steam catalog to Linux and Mac computers without the need for complex technical tricks.

Yes, Steam's in-home streaming truly feels like magic, even though it's not quite perfect yet. And once you've played a beastly modern game on a crusty old laptop that normally starts dropping frames when the word "Battlefield" is merely uttered, I'm sure you'll agree.