While we typically follow a standard formula for our Build It section every month, sometimes it's nice to deviate a bit from the norm and explore different types of systems that are a bit more unconventional. One such system is the type of build we use at Maximum PC HQ for testing hardware, known as the open-air test bench. We have several of them deployed throughout the office alongside our standard-issue desktop PCs, and both types of machines serve an important purpose. The standard desktops are great for YouTube and Reddit, and occasional “work,” while the open-air test benches are used for most of our component testing since they let us swap a video card, CPU, SSD, RAM stick, or even the entire motherboard with minimal effort. When you’re using an open test bench setup on top of a desk, you’ll never again have to dig through the guts of your computer while on your hands and knees, with a flashlight clenched in your teeth. All you need to set up one for yourself is a basic set of spare parts, and it will let you operate like a civilized gentleperson, from the comfort of a chair, without breaking a sweat. With that in mind, we thought we would show you how to build an open air test bench PC!
Thinking Outside the Case
There are a lot of reasons any died-in-the-wool hardware enthusiast would want to have a test bench up and running at all times. The most obvious is that it’s great for quickly testing a stick of RAM, a malfunctioning piece of hardware, or benchmarking hardware outside of a system that needs to be used for productivity. At Maximum PC, our bench of choice is the Top Deck Tech Station Kit made by HighSpeed PC ($140, www.highspeedpc.com). This is a two-tier workbench, where the motherboard sits on the upper tray, and the power supply and storage devices (or other external bay items) sit on the lower tier. The station’s legs, rails, and PCI-card support brace are all made of sturdy and nonconductive materials, and the kit supports a decent amount of hardware, too. The top of the tray looks just like a standard motherboard tray in that it has rubber standoffs for clearance. A nylon guide post helps you align add-on cards with their slots in the motherboard, and a bundled neoprene mat helps prevent items in the lower tray from sliding around. In place of your case’s power and reset switches, there are switches you plug into the board's front-panel connectors that allow you to turn the machine on, reboot, monitor drive activity, and hear the PC speaker. Yes, they are pricey, but very durable and able to accommodate hardware not even conceived of yet, due to their open-air design and flexibility. As always, there are several things to consider before diving in, so let’s take a look at what’s involved in letting your hardware go commando.
1. On the Rails
Storage devices slide into rails pre-installed on the underside of the upper tray, and they only accommodate 3.5-inch drives. The rails also have no holes for drive screws, by design—you just slide the drive in, then slide it out when you're done. If you want to install an SSD, you'll need to order a 2.5-inch rail kit separately at HighSpeedPC.com. Or you can skip the adapter, since SSDs don't need to be near the 120mm fan that cools the devices in that area, and since they have no moving parts they don’t need to be stabilized at all times like a spinning hard drive. The rails are long enough to support two 3.5-inch drives, and we put SSDs on the lower tray dangling from their SATA power cables.
2. More Able Cables
A modular power supply is extremely useful when trying to keep your cables organized in an open test bench. If you’re not using an optical drive, there's plenty of space in the lower tray alongside the power supply to store the bag that contains the unused cables. Orienting the power supply can be a little tricky, since the 8-pin CPU power cable has to go to the top of the board, the 24-pin motherboard cable goes to the side, and the SATA power cables go to the bottom. Therefore, our preferred setup is to have the cables going toward the top of the motherboard, and the AC power plug facing the "bottom" of the motherboard. We also recommend using a stock CPU cooler since it makes accessing the area around the CPU easier, and if you can, just use the CPU's integrated graphics since it gives you one less PCI Express power cable to deal with. If we're testing a CPU without integrated graphics, we just use an old GPU that doesn’t require PCIe power.
Click on page two for the rest of the instructions on how to build an open-air test bench PC.
3. Pushing Buttons
The buttons and lights on the front of an ATX case are very useful, and allow you to turn on your system, reboot it, and watch CPU and hard-drive activity. Open-air benches have similar buttons and lights—on this model it’s called the ATX control kit and features a set of buttons and LEDs that plug into the motherboard's front-panel connectors. It even comes with a PC speaker, so you can hear beep codes in order to help you diagnose hardware issues (unless your motherboard has a debug LED on it, making the speaker redundant). You could always short the power-on circuit yourself with a knife blade, but this is more… dignified.
4. Feeling Pinched
The top tray has an array of standoffs that accommodate ATX, eATX, Mini-ITX, and microATX motherboards. The standoffs sit inside rubberized feet secured with Phillips screws, so you can easily pop them out of one spot and stick them into another. No screws actually touch the motherboard, of course; it just sits on top of the rubber feet. Again, this is by design, to make it easier to swap one board for another. It does complicate plugging in power cables though, as pressing down on one edge of the board can raise the other side. When the connector is large, like with the 24-pin power cable, you have to pinch the top and bottom of the board at the same time, sandwiching the connector, as shown in the photo. When the connector is small, like a USB 2.0 cable, you can just support the board from below with your hand, right underneath where the connector is going in.
5. Getting Some Air
Thanks to the open design of this workbench, there are no limitations to the length of PCI cards (handy when Nvidia and AMD deliver the latest 12-inch monsters). Cards are slid into their expansion slots and secured to the support bracket with the included plastic screws. The support brace is supported by metal posts but is made of plastic to help prevent static discharge. There are a total of seven screw holes in the bracket, which should be more than enough for any mobo configuration.
Once a video card, hard drive, or RAID controller is installed, you may want to add additional cooling that would normally occur by virtue of a case’s airflow, but is lacking in this setup. Your best bet is to just place a 120mm fan on the top tray to move air across the components — jerry-rigged, maybe, but effective. Since the fans are easily accessible, we like being able to control fan speeds with a fan mate, which is an inline fan speed controller. HighSpeed PC also sells extension kits for mounting additional fans on the rim of the upper tray, but we’ve never felt the need to add that much cooling.
6. Dat Masscool
The workbench comes with a pre-installed 120mm Masscool fan with a grill that is mounted in between the bench’s two tiers, so it blows air over the top and bottom of the tray, hitting the motherboard and any storage devices sitting in the rails below. The fan is universally compatible too, sporting both a 3-pin and a 4-pin Molex cable, so it’ll work with any setup you have. That single fan should provide more than sufficient cooling for a basic workbench. It’s surprisingly quiet, but we also use the onboard fan control in our system BIOS to make sure it’s silent.
The ATX control kit is not bad, either. Each of the widgets has an embossed triangle indicating the positive wire, so connecting them is simple. It won't damage anything if you install them incorrectly; they simply won't work. Things got a bit tight on our test board when we tried to plug in the semi-stiff PC speaker widget, so we left it off. The workbench also includes an expansion bracket with both power and reset buttons, but it’s really cheap and its wires are a rat’s nest.
It probably takes longer to assemble the workbench than it does to install all of its hardware, but once you remove a conventional case from the equation, building goes 10 times faster. You have superior lighting and there is minimal cable management to work out. We also love not having to worry about feeling crowded or lacking in space when building these rigs. There are some downsides, though. This workbench doesn't really allow liquid cooling, as there’s nowhere to mount the radiator. It would also be nice to have a couple of fasteners to pin down the motherboard, and we’d love to have an SSD rail included instead of it being an expensive add-on. Also, $140 is a lot of money, but HSPC also sells a smaller ATX bench for $80 that will be fine for most users.
Probably the biggest problem with these setups is the exposed fan blades on the CPU, GPU, and chassis. We can already see a small child or a pet getting in trouble around this thing, so be sure to take precautions before deploying one in your home.