The current hotness in the world of gaming is enabling portable in-home gaming by leveraging your screaming-fast non-portable hardware. The Wii U has gamepad play, Sony’s got PS Now, and Valve has recently launched a beta of their “In-Home Streaming” feature for Steam. I recently got a beta invite, so I sat down with my hardware to figure out what’s what.

The Hardware Setup

My house is on a wireless network, with the router being a TP-Link Archer C7. (My review of this router can be found here) This is a 802.11ac router, which is one generation newer than 802.11n. I’ve got three PCs that I will be testing with the Steam in-home streaming beta as part of this article.

Here are the specs:

Desktop Laptop #1 Laptop #2 CPU Intel Core i5-3470 (Ivy Bridge), 4 cores at 3.2GHz AMD Phenom II P920, 4 cores at 1.6GHz Intel Core i5-3210M, 2 cores (4 threads) at 2.5GHz GPU Radeon 7950 Radeon 5650 Intel 4000-series Monitor ViewSonic 1920×1080 Integrated 17″ 1366×768 panel Integrated 14″ 1366×768 panel RAM 8GB DDR3 1600 8GB DDR3 1600 8GB DDR3 1600 Disk 128GB Samsung 840 Pro SSD 128GB Samsung 840 Pro SSD 500GB Western Digital 5400 RPM HDD Wireless Net TP-Link 802.11ac PCIe Integrated 802.11n Integrated 802.11n

In addition to the wireless network, I’ve also got a 100Mbit switch on my desk that I will be using for the wired tests.

My gaming rig was updated about a year ago, and was pretty much a “best performance for the money” I could manage at that point. Laptop #1 was my stalwart gaming machine for a few years running. It kept up OK with most games, although it’s not going to be knocking your socks off with its performance these days. Laptop #2 is one that I bought with the intention of moving around the house with, but not really playing games too much on.

My hypothesis going in was that Laptop #1 was going to play the Steam in-home streaming beta with flying colors, and that Laptop #2 ought to do OK, given that it is relatively recent vintage and really what I would want to buy or use for playing games elsewhere in the house.

Steam In-Home Streaming Beta Client

To get into the beta, you’ve got to join the Steam Community group and then wait patiently for an invite. Once you’ve got an invite, you go into the “Steam” menu, choose “Settings” and on the “Account” panel, set your Beta participation to “Steam Beta Update.” Steam will download a big update and then restart.

Once you’ve finished these steps, you’ve got to log into Steam on multiple computers under the same account. Each time another PC logs in to the same account on your network, you get a little popup in the lower right informing you of the new PC.

This is the first major change I noticed versus the standard client. Steam actually allows you to be logged in to multiple computers at once, finally! It doesn’t boot you off and disconnect you from the chat interface and so forth any time you log in on another PC.

Once you have logged in, you can browse your Steam library as you normally would. When you look at the library, however, you’ll see not only the games you have installed locally, but also any games you have installed on any PC logged into that same account.

I was also able to log in in “offline mode” on the second PC, and still see the streaming games on my primary PC. It’s a small thing, but it’s still pretty cool.

The “Play Game” button has been replaced with a little drop-down, which allows you to choose what you want to do with a particular game. You can opt to install and/or play it locally, or you can choose to install or play it via streaming it from another PC.

If you opt to use the Steam in-home streaming beta to stream a game, the host PC will launch the game normally, and then after a short delay the target PC will be showing the game as well. One bummer is that you can’t do anything else on the host PC while the game is being streamed to another PC. Although the host PC will respond to your input, if you Alt-Tab to another program, the other PC will reflect this change as well. Thus, you’re essentially dedicating two screens to showing the same content.

When in-game, both sets of input devices work fine for controlling the game. I could see this being yet another option for people who like to play “shared keyboard/mouse” input games like Surgeon Simulator or similar.

Steam In-Home Streaming Performance

Okay, time for the stats porn. I’ve collected a small set of games to test with, picked primarily by what I already had installed, because I am lazy. What I’ve got here is:

Deus Ex: Human Revolution – I’m in Detroit, just outside the police station. Laptop #1 had real trouble rendering the external scenes in this game, so it will be interesting to see how streaming it from my desktop works.

– I’m in Detroit, just outside the police station. Laptop #1 had real trouble rendering the external scenes in this game, so it will be interesting to see how streaming it from my desktop works. TES5: Skyrim – I’m in Riften, and I’ll be testing Steam in-home streaming by moving around outdoors and playing in the water.

– I’m in Riften, and I’ll be testing Steam in-home streaming by moving around outdoors and playing in the water. Super Meat Boy – I’m super terrible at this game, but I’m going to use it as an “input lag” benchmark by playing some easy levels and seeing how I do.

Test 1: 1366×768 on 100mbit private LAN

Game Desktop Settings Laptop #1 Performance Laptop #2 Performance Skyrim 1920×1080, Ultra, No graphical mods, 30 fps 0% frame loss, completely playable 0% frame loss, completely playable Deus Ex: Human Revolution 1366×768, MLAA/Trilinear/Normal, 60 fps 5-10% frame loss, some input lag Desktop throttled to 30fps, <5% frame loss, minor input lag Super Meat Boy 1366×768, 50-60 fps 3-5% frame loss, still very playable <1% frame loss, completely playable

Skyrim was smooth as glass in this test. Given that all the rendering is done on the desktop, I wouldn’t expect settings to matter much. If your rig can handle a given set of settings for a game with a bit of overhead, the performance over Steam in-home streaming should be similar.

Deus Ex was a bit tougher – it doesn’t seem like the system can quite get to 60fps. The desktop can render at that rate, and there’s certainly network bandwidth to spare here, according to the stats. I don’t know if it’s a decode limitation on the laptop(s), but I wouldn’t think so. I tested a lower resolution, but I imagine that the captured video is being scaled before being streamed. Thus, since the desktop can handle the higher resolution fine, it doesn’t really make a difference.

Surprisingly, I didn’t notice any significant input lag with Super Meat Boy, even though there was a bit of frame loss. The jitter was a bit jarring, but it wasn’t unplayable by any stretch of the imagination. If you’re tackling a particularly hard level, you probably want all the advantages you can get, though. Thus, I don’t know that it would be a good go-to solution for this type of game.

Test 2: 1366×768 on Wireless (802.11n for Laptops, 802.11ac for Desktop)

Game Desktop Settings Laptop #1 Performance Laptop #2 Performance Skyrim 1920×1080, Ultra, 30 fps 30-50% frame loss, lots of hanging and stuttering 0% frame loss, completely playable Deus Ex: Human Revolution 1366×768, MLAA/Trilinear/Normal, 60 fps Desktop throttled to 30fps, 50% frame loss, lots of hanging and stuttering Desktop throttled to 30fps, <1% frame loss, completely playable Super Meat Boy 1366×768, 60 fps Desktop throttled to 15 fps, 30-50% frame loss, unplayable <1% frame loss, completely playable

Yikes. You’ll notice here that for the Laptop #1 tests, the frame rates on the desktop have tanked – the Steam in-home streaming client isn’t attempting 60fps anymore in either Deus Ex or Meat Boy. Not only that, the streaming performance is in the toilet as well. I’d expect roughly the same amount of load on the desktop machine in both the wired and wireless configurations. Are some bad wireless drivers are to blame here?

Laptop #2 fares much better, despite its underpowered integrated GPU. I’m not sure if I should credit the more modern CPU architecture or better wireless chipset/driver here. It’s good news for integrated Intel GPU owners, though!

Test 3: 1080p TV on Wired

Both of the previous tests were roughly 720p resolution, which is the old and busted by even a couple of years ago’s standards. I don’t have a 4k by 2k setup here, but I do have some 1080p TVs. The scenario here would be that your gaming desktop is in one room, and you want to stream games from there to a lower-powered computer in another room.

Since I’m using the same networks and the only difference is the resolution of the display, I’m not going to re-run the Super Meat Boy tests. We’ve established already that the input lag is acceptable when the streaming is behaving.

Game Desktop Settings Laptop #1 Performance Laptop #2 Performance Skyrim 1920×1080, Ultra, 30 fps Desktop throttled to 20 fps, 0% frame loss, completely playable Desktop throttled to 20 fps, 0% frame loss, completely playable Deus Ex: Human Revolution 1920×1080, MLAA/Trilinear/Normal, 60 fps Desktop throttled to 30fps, <1% frame loss, completely playable Desktop throttled to 30fps, <1% frame loss, completely playable

For the 1080p test on Laptop #1, I had to manually override the settings in the Steam In-Home Streaming settings page. The “automatic” resolution setting was trying to limit the stream to 720p. It’s clear that Valve doesn’t think my hardware is capable of giving a good experience at the higher resolution. However, things seem to be OK on wired.

Test 4: 1080p TV on Wireless

Since we’ve already established that laptop #1 has some wireless issues, for this test I’ll introduce a 802.11g-based wireless bridge. Thus, laptop #1 will be using its 100mbit NIC instead of the integrated wireless.

Game Desktop Settings Laptop #1 Performance Laptop #2 Performance Skyrim 1920×1080, Ultra, 30 fps Desktop throttled to 20fps, a bit of stuttering, but mostly playable Desktop throttled to 15-20 fps, Lots of stuttering and freezing Deus Ex: Human Revolution 1920×1080, MLAA/Trilinear/Normal, 60 fps Desktop throttled to 20, then 15 fps, a bit of stuttering and freezing Desktop throttled to 20, then 15 fps, a bit of stuttering and freezing

Weirdly enough, on this test Deus Ex is performing a bit better than Skyrim. 1080p at 30fps seems to be a bit much for these laptops though, even on the newer laptop that didn’t have any issues with a lower resolution.

Graphical Comparisons: 1366×768

I captured some screenshots from Deus Ex and from Skyrim to do some head-to-head comparisons. The streamed shots were taken from Laptop #1 during the LAN test, and the video bitrate was roughly 14 Mbit/s. That’s a pretty decent bitrate assuming they’re doing some reasonable compression.

During these tests, the laptop was running 1366×768 and the desktop was running at 1920×1080. Thus, I scaled down the desktop screenshots with cubic interpolation, overlaid the two, and then upscaled the comparison shot by a factor of 2 with no interpolation to show a bit more detail.

On the left is the image from the desktop, and the right is the streamed image from the laptop.

Since I’m processing these images and then compressing these to JPG, there might be some loss of quality, or you might disagree with my image quality methodology. Thus, I’ve uploaded the raw BMP files for you to evaluate for yourselves here. The

My day job involves a lot of evaluation of streaming video quality, and I can’t tell the difference here. I assume that what they’re doing is taking the rendered frame from the desktop’s GPU, then scaling it to the laptop’s resolution, compressing it, and sending it to the laptop for decompression and display.

If this is indeed the case, the only loss in quality would be in the scaling and compression. Since there are fewer pixels in my laptop configurations, scaling is kind of a given. The high video bitrate for compression means that the quality level is generally preserved well. It’s possible to adjust the bitrate and the maximum streaming resolution in the settings, which will decrease the quality but go a little easier on your hardware and network infrastructure.

Graphical Comparisons: 1920×1080

During the 1080p TV LAN tests, I grabbed some additional screenshots. The compression artifacts are starting to get pretty noticeable at 1080p. This is kind of the “best case scenario” with the LAN involved, too. There’s plenty of bandwidth, but the video data rates are similar to the 1366×768 case. I’m guessing that Valve has set a maximum bitrate here, and it’s not quite enough for 1080p to look super good while streaming.

Again, on the left is the source frame from the desktop, and on the right is the frame seen on the laptop post-decode. The sign is yellow and black, and for the most part you can see that on the left. On the right, you start to see some blues and reds creeping in, and you can see that the color of the sign itself isn’t 100% consistent. These are all bitrate-related compression artifacts.

It’s not really noticeable in the screenshots in Skyrim, but it is noticeable in the live video while playing. The textures on the buildings seem to shift a bit as you look at them or pan back and forth.

I don’t think these artifacts would be super bothersome if you were sitting on a couch a distance away from your TV, but if you’re streaming to a 1080p monitor close to your face you’d probably notice them. If you’re going for the highest fidelity graphics, this streaming setup might not be the best option.

Impressions and Conclusions

There were a few glitches and gotchas I encountered that marred the experience somewhat. Hopefully these are just bugs that will get squashed in a later release of the beta before it ships, but time will tell: