Manufacturers have tried to put PCs in our living room for years, with mixed success. One of the most recent example is Alienware's X51, which looks great in a home-theater rack, but delivers underwhelming performance when you use it to play high-end games with all their graphic settings cranked up.

But this January, the "PC as a gaming console" construct took a new twist. Valve Software, the developer of the Half-Life game series and Steam digital distribution network, confirmed long-running rumors that it's working on a "Steam box"--a prebuilt PC that plugs into an HDTV, and runs the entire lengthy list of games available on Valve's network. But there won't just be one Steam Box on the market. Instead, the Steam Box will become its own hardware category, filled with prefab PCs from multiple manufacturers and endorsed by Valve.

At CES 2013 in January, we saw the first of many Steam Box PCs to come when modular PC manufacturer Xi3 debuted the Piston, a prototype PC designed with input (and financial investment) from Valve.

Built to fit inside a home entertainment center, the Piston looks cool; but with its expected AMD APU, it probably won't be able to run demanding PC games on a big HDTV without serious performance problems.

So if you want to play games like Borderlands 2, Hawken, or the upcoming Bioshock Infinity at peak performance, you'll need more power than the current Steam Box prototypes seem capable of providing. To that end, I set out to build a compact gaming PC that would sit in my home-theater component rack and deliver a great couch gaming experience.

Gaming PCs don't fit in the living room

What I plan to build is a compact gaming PC capable of delivering 60 frames per second at full HD resolution: 1920 by 1080 pixels. Sure, most console games can't reach 60 fps consistently, but some can; and to compete with consoles, a living-room gaming PC needs to hit that magic frame rate.

The problem is the inherent shortcomings of compact PCs: limited expansion, limited power, and reduced heat dissipation. In particular, the small volume inside a compact case greatly complicates the task of dissipating the heat generated by fast CPUs and GPUs without generating a ton of fan noise.

The good news is that the system needs to hit high frame rates only at 1080p resolution--child's play for contemporary high-performance PC components. Also welcome is the fact that modern PC components are incredibly quiet and power-efficient; thus, the right mix of components in the perfect case makes a high-performance Steam box in the living room possible.

Researching the appropriate set of components--particularly choosing the right power supply and the best case--proved challenging. In the end, however, I assembled a stack of excellent components that can deliver good performance at reduced noise and with modest power requirements.

CPU and GPU: The heart of the matter

Current home consoles pack fairly outdated hardware, so I don't need to invest in a cutting-edge CPU and graphics card to get a solid gaming experience. I do need a power-efficient CPU + GPU combination that can deliver great gaming performance on higher-end titles like Far Cry 3.

CPU - Intel Core i7-3770s: The 3770s is a quad-core, Ivy Bridge processor running at a base clock of 3.1GHz. Like other desktop i7 CPUs, it supports up to eight threads using Intel's Hyper-Threading technology. Even though it's a quad-core CPU running at over 3GHz, its nominal power rating is 65 watts. Unlike the higher-end 3770K, the 3770s is multiplier locked, so overclocking isn't as easy. But in a small case, you won't want to overclock much anyway.

Graphics card - Asus GTX 660 Ti: Good performance, low noise, and power efficiency in one graphics card are hard to find, but the Asus GTX 660 Ti DirectCU II fits the bill nicely. The dual fans spin fairly slowly, so fan noise is minimal, even under a heavy gaming load. The GTX 660 Ti GPU does a fine job with gaming at 1080p resolutions, even in demanding titles. The 2GD5 model runs the GPU core at 915MHz, but it can boost the clock frequency to 980MHz when needed. The GTX 660 Ti also comes loaded with 2GB of GDDR5 memory running at 6008MHz (effective). The 192-bit memory interface might be a limiting factor if you're turning on high levels of antialiasing, but it should be more than adequate for most 1080p gaming. Even better, this card has a rated power draw of 150 watts under load and just 12 watts when idling.

An efficient platform

With the graphics and CPU choices made, let's turn to the platform: motherboard, memory, case, and power supply. The motherboard must support the LGA 1155 Core i7 3770s CPU, and will dictate the physical size of the case. The system needs an adequate amount of memory, and anything to help power efficiency is a bonus. The case should be small enough to sit on my A/V rack, but large enough to ensure adequate airflow. Finally, the power supply must be efficient and quiet.

Motherboard - Asus P8Z77-I: This Steam box runs on an Asus P8Z77-I Mini-ITX mainboard. The P8Z77-I sports two DDR3 memory sockets, on-board Wi-Fi with Intel WiDi (Wireless Display) capability, Bluetooth, and a bunch of USB ports. One cool design decision by Asus was to put the VRMs (voltage regulator modules) on a separate riser board on one side. The riser board is attached with screws that also serve as mounting screws when you attach the entire affair to the bottom of the case. The rear of the board includes graphics ports (in case you're using integrated graphics), USB ports, and antenna connections for Wi-Fi.

That's a nice feature set, but the strongest reason to pick the P8Z77-I is its compact size: We can build this Mini-ITX board into a really small chassis. The board also has one PCI Express X16 slot for a high-performance graphics card, so it can accommodate the GTX 660 Ti just fine.

Memory - HyperX LoVo DDR3 RAM: I've used Kingston HyperX LoVo low-voltage DDR3 in past projects, and it has consistently delivered good performance. At 1.35 volts, it demands less power than the typical 1.5 volts required by standard DDR3 and much less than the 1.65 volts that some high performance modules need. Yet the price premium over standard DDR3 is fairly modest. An 8GB kit consisting of two 4GB modules costs less than $60, which is competitive with the prices of other high-quality DDR3 modules.

Case - Coolermaster Elite 120 Advanced: The numerous Mini-ITX motherboards available have spawned a large number of compact cases. In an ideal world, I would have found a suitable low-profile case, but in the world we've got I would have had to sacrifice too much graphics performance to get the dimensions I preferred. In the end, I narrowed my options down to three cases: the Silverstone SG06, the Fractal Designs Node 304, and the Coolermaster Elite 120 Advanced. The SG06 was the smallest of these, but I had concerns about the 300W power supply, and the 10-inch Asus graphics card looked problematic, too. The Node 304 is pretty massive for a Mini-ITX case, yet it lacked an optical drive slot (it would have been a great choice if I had been building a small server). The Coolermaster Elite 120 Advanced is almost as large as the Fractal Design case, but it's the one I chose in the end.

The Elite 120 can handle a 10.5-inch graphics card; and since the Asus GTX 660 Ti is a nonreference card that's a bit longer than most, having the extra space proved useful. The Coolermaster also accepts a full-size ATX power supply and full-size optical drive. Tool-free installation of storage hardware is an added bonus.

Power supply - Seasonic SS520-FL: High efficiency and low noise are key requirements for a power supply destined for service in in a living-room PC. Seasonic's SS520-FL is a passively cooled, fanless power supply with an 80-Plus Platinum efficiency rating--meaning that the SS520-FL is 90 percent efficient through most of its range, dipping below 90 percent (to 89 percent) efficiency only under 100 percent load. My little Steam box will never demand 100 percent from a 520-watt PSU, so it should perform at peak efficiency.

The Seasonic PSU offers the added benefit of having modular connectors, so I could install only the power connections I needed. As it turns out, I ended up needing most of them, but I was able to leave one aside. And any reduction in power-supply cabling means less clutter and better airflow through the already crowded case.

For the CPU cooler, I needed something compact and quiet, and yet able to get the job done. Silverstone makes a low-profile LGA 1155 cooler, the NT07-1156, that can handle CPUs rated at up to 95 watts. It also has a small switch on the side to run the fan a little more slowly, for lower noise. That's what I used for the 65W Core i7-3770s CPU.


Primary hard drive - Crucial M4 512GB SSD: Given that my Steam box will be running games, the system must offer enough storage to hold a number of games--and modern PC titles can consume a lot of space. At the same time, low power and low noise are essential. I went with the Crucial M4 512GB solid-state drive. I've used this SSD in other systems, and it's been admirably reliable. It's not the best-performing SSD you can buy, but it's relatively inexpensive, at under $400, and it's plenty fast for my needs, especially when compared to the standard disk-based hard drives found in most PCs and gaming consoles.

Optical drive - Asus BW-12B1ST Blu-ray: If I were running nothing but Steam games, the system wouldn't need an optical drive. But I occasionally buy games on optical media, and not all great games are sold on Steam (yet). By dropping in a Blu-ray drive, I can also use the system to play Blu-ray movies on the 60-inch LG plasma HDTV hooked up to this PC. I chose the $80 Asus BW-12B1ST Blu-ray writer because it packs a lot of capability into a Blu-ray drive, including 8-12X Blu-ray write speed and 16X DVD-R write speed.

Gaming hardware

Since the Steam box is positioned as a kind of game console, I need good controllers for my version. As for any PC, you'll want a good wireless keyboard and mouse, but they don't need to be the hottest gaming peripherals around. Bluetooth keyboards won't work well, as the range in a typical living room makes Bluetooth gear a bit unreliable. In the end, I settled on Logitech's Wireless Combo M520. It gets the job done and uses a single, tiny USB radio receiver.

For games that require analog sticks, Microsoft makes the Xbox 360 Wireless Controller for Windows. This is exactly the same controller layout used with the actual Xbox 360 controllers, so it's immediately familiar. It works great when navigating Steam's Big Picture full-screen mode, and it's a solid controller for action games.

The price of PC gaming

How much does all this gaming goodness cost? Let's break down the pricing for all the components. (Note that pricing is calculated at time of publication and excludes any sales tax and shipping costs.)

The total cost is $1675, including keyboard, Windows 8, and game controllers.

Some assembly required

I'm not going to cover all aspects of building this PC in depth, but I will cover key aspects that differ from PCWorld's $1000 gaming PC that I built recently.

Building into a tiny case involves some creative thinking about the order of assembly. For example, you'll want to put the PSU in last, since it blocks access to most of the internals.

Before you do anything else, make sure that the case itself is prepped. First, install the motherboard standoffs in the bottom of the case; they don't come preinstalled. The standoffs require some effort to screw in, so you may want to use a small (5mm) hex nut driver to screw them in.

You can also preinstall the solid-state drive and Blu-ray drive, since the storage bays are in front of the motherboard compartment and don't overlap it. The Coolermaster case is mostly tool free, but SSDs do require insertion of small screws, since the hard-drive brackets work in tool-free mode only with 3.5-inch hard drives, not 2.5-inch SSDs. The optical drive slides in and latches into place without screws.

You'll then install the memory and the CPU into their respective sockets before dropping the motherboard into the case. Asus preinstalls the Wi-Fi card, so you won't have to fiddle with that chore. We're not using the stock Intel cooler, so you'll have apply thermal paste, but you won't need to provide your own because the Silverstone CPU cooler comes with a small amount of it.

Use just a small drop of paste, and spread it over the surface of the CPU heat spreader with a flat-bladed screwdriver or craft knife. After adding the paste, attach the CPU cooler itself. Like the standard Intel cooler, the NT-07 uses latches that lock into small holes surrounding the CPU when you press the latches down. Make sure that you feel a firm click when pressing down the latch. Also, remember to attach the power connector for the fan to the proper connector on the motherboard.

Finally, make sure that you insert the ATX I/O shield into the case opening provided for it!

Installing the motherboard

Installing the Asus P8Z77-I motherboard differs somewhat from installing most PC motherboards. The VRM module is on a separate riser board that screws onto the motherboard itself. Those screws exactly overlap the standoffs that are used to attach the motherboard to the case. Start by removing the screws holding in the VRM module, being careful not to detach the module from the motherboard. Retain both of the screws; you'll need them next. (You can, however, discard the retaining nut that held the screws in place prior to your removing them.)

Next, slide the motherboard into the case, aligning the holes with the standoffs underneath. You can use the screws included with the Coolermaster case for the pair of standoffs opposite the VRM module, but you'll want to use the screws you removed earlier (it sounds more complicated than it really is).

Now attach the internal wiring. Start by attaching all of the front-panel wires to the adapter that Asus thoughtfully provides; then plug the adapter into the motherboard itself. This process is much easier than trying to install each individual switch connector to the motherboard.

Remember to install the USB front-panel connectors, too. New motherboards and modern cases often have two different types of connections: one for USB 3.0 front-panel ports and another for USB 2.0 ports. The USB 3.0 type is bulkier and the cabling is often stiff, so routing and aligning the connector is something of a chore. Also, if you plan to use headphones, don't forget to install the audio front-panel connector.

After the motherboard is in place, you'll need to prep for the power supply installation. This is where the modular connectors used in the Seasonic PSU are a godsend, because you attach both the main, 24-pin power connector and the eight-pin ATX12V CPU power connector to the motherboard. Again, you should do this before you install the PSU. You may also want to attach the power and SATA data cables to the SSD and optical drive at this point.

Attach the side-case fan power connector to the second fan connector on the motherboard. This is adjacent to the CPU fan connector. Unfortunately, the Asus board lacks a third fan connector, so the front-panel fan will have to be powered by a dedicated four-pin connection from the power supply itself.

Installing the power supply and graphics card

Now, before you slide the power supply into the case, attach all of the power supply connectors that you've attached to the internals of the system to the PSU. The whole affair is a bit messy looking, but it will make life much easier very soon. Since you haven't installed the graphics card yet, you may want to attach the PCIe graphics power connectors to the power supply as well. The last connector you'll need is the old-style Molex four-pin power connector that you'll be using for the case fan.

The Coolermaster case includes a power-supply extension that protrudes out the back. Detach it (by removing four screws), attach it to the power supply, and then slide the entire assembly back into the case.

Slide the power supply into the case slowly, routing the bulky main cable as you push in the PSU body. The Elite 120 case has plenty of internal room for routing the long power cables so they're out of the way. Make sure that nothing blocks the CPU fan, as you want it to spin freely. Once the PSU is in place, dress any remaining wires and cables before installing the graphics card. That will make everything look neater, as well as keeping stray wires out of the fans and improving airflow.

Remove the two back-case brackets in preparation for installing the graphics card. The graphics card is long, and you'll need to align and wiggle it a bit. The trick is to get the top of the card bracket under the overhang on the open slots while angling the card just a bit toward the case side so that you can align the connector to the PCI Express slot. Work carefully, as the front-panel audio motherboard connector barely fits underneath a cutout on the graphics card connector.

Final setup

Your final steps are to fire up the system and test that everything's installed properly. I do all of my initial testing prior to attaching the top shell on the case, so I can quickly move wires around that may be blocking fans. Once the initial testing is complete, I install Windows 8 onto the SSD. The most tedious part of the entire process involves installing all of the drivers and Windows updates. Only then do I attach the case shell to the case, completing the main build.

Once I had completed the Windows setup stuff, I carried the box out to my living room. The system attaches to my Onkyo receiver via a single HDMI cable, which handles both graphics and audio.

I had to fiddle with Steam a bit to make it automatically log on to my account and start in Big Picture mode. So far, I've played Borderlands 2 and Torchlight 2 using the Xbox 360 PC controller, and it's all been smooth as silk. I'm not great with a console-style controller, but everything seems to work pretty well. My only real complaint is that I wish the Xbox controller also worked with the Windows 8 Start screen, but you'll need a mouse, keyboard, or touchpad for Windows navigation.

After running the system for a few hours, I'll probably replace the front fan on the case with a slower, quieter fan such as the 800-rpm or 1200-rpm Scythe S-flex fans. The Coolermaster fan's noise is just barely noticeable, but you can hear it when the system is idling. In-game, however, the booming multichannel audio drowns out any PC noise. The system idles at 49 watts, but I'm sure I can lower the idle power by a few watts with a little tweaking.

At $1675, this is a fairly pricey little PC, but it looks good and it offers an uncompromising HDTV gaming experience. I'm sure it will compare favorably with the fabled Steam boxes (which may start hitting the market this year) from Xi3 and other hardware vendors--and my machine will continue to perform well in future games--at least, until I upgrade to a 4K HDTV.