Component choice
Things to consider when picking parts for your Linux PC.
Desktop case
Cases come in all shapes and sizes. The mini ITX form factor is popular, and is ideal for home-theatre PCs. However, the more compact cases won’t admit a full-size ATX graphics card, optical drives, or even 3.5-inch drives in some cases. Furthermore, one needs to consider airflow. Choosing an ITX case may restrict you to an SFX power supply, and smaller motherboards tend to lack features, with fewer PCIe slots and SATA connectors than their counterparts. But for the right price, you’ll be able to find what you need.
Traditional ATX tower cases are the easiest to work with and have plenty of space for drives and lengthy graphics cards (high-end ones can get close to 300mm, so be sure to check your measurements). Depending on your taste, you may want a case with a side window, and possibly some stylish/garish “cold fluro” UV tube lighting. Some cases are engineered with quiet operation in mind, and include soundproofing and vibration dampening grommets for mounting your hard drives.
Power supply
Today’s chips and graphics cards can pull a huge amount of power, and bad things will happen if your PSU can’t supply the juice. A modest setup is unlikely to draw more than 300W, but it’s worth investing in a larger-capacity unit, since PSUs tend to find optimum efficiency at around 50 per cent capacity. High school physics taught us that transformers in general are pretty efficient, but the more expensive, 80+ bronze, gold and platinum PSUs feature ones that are especially so, offering up to 94 per cent efficiency in the best case. That means less heat emitted, less need for fans and a smaller chance of combustion.
Modular power supplies include detachable cables, so only those that are required need be attached. This improves tidiness and airflow. A high-end graphics card will draw 250W under load and a high-end CPU (such as Intel’s i9 7900X) may pull another 150W. So this setup warrants at least a 750W PSU. USB devices, cooling and internal drives consume much less power, so don’t really factor into this calculation. Because multi-GPU setups are becoming common (as much for cryptocurrency mining as for gaming) it’s easy to understand the higher capacity offerings here.
Motherboard & RAM
The motherboard is what everything plugs into, at its core is the main chipset that defines the processor socket it uses (Intel or AMD) and its other features. Chipsets generally span high-, mid- and low-end budgets. For example the AMD Budget A320 chipset doesn’t support overlocking and has limited SATA and PCI-e lanes. The mid-range B350 and highend X370, subsequently offers more and more of everything. For Intel the latest Coffee Lake 8th-gen CPUs require a Z370 mobo, previous Socket 1151 processors require a 270, 170, 150 or 110 series chipset on the motherboard.
RAM is cheap nowadays. Nevermind if you can clean boot into Sway using only 20MB. As soon as you open up a couple of pretty websites in Chromium you’ll be chowing down the best part of a gigabyte. Add to that a couple of VMs (everyone loves testing distros in VMs) and you’ll get to our
recommended entry-level figure of 8GB. Go for 16GB if you can afford it, and 32GB if you need it. If your OS runs out of memory or swap space, then the OOM killer kicks in and ungracefully terminates processes until the panic is over. This, understandably, can have undesired side-effects, so don’t scrimp on RAM. Newer systems use DDR4 memory; the fastest one available now runs at 3200MHz, but barring some serious applications and synthetic benchmarks, you won’t notice any advantage over lower speeds. Motherboards supporting the older DDR3 standard (and older CPU sockets such as the antiquated AM3+ and the middle-aged but weary LGA1150) and are being phased out, but some retailers have some clearance bargains.
Processor
Until AMD released its new Zen architecture last year, the only reason for choosing its silicon was to save money. If you wanted performance, be it for games, number crunching or running VMs, Intel was your only choice. While Intel is probably still best for gaming (the i5 8400 offers great value for around £200), AMD’s new ThreadRipper (TR) chips are great for tearing through computationally heavy workloads (like mining XMR). TR chips start at £500 for the eight-core and its flagship consumer chip, the 16-core 1950X, will set you back very close to £1,000.
The Ryzen series, were a gamechanger for AMD. The eightcore Ryzen 7 1800X can be had for £400. The Ryzen 5 series offers great value for money, starting at £140 and competing with Intel’s latest Core i3s. Intel’s high-end offerings, the Octo Core i7 Skylake X series, start at £540, but at the higher end of the scale you’ll find 12- to 18-core i9s for between £1,000 and £2,000. AMD’s flagship consumer chip, the 16-core 1950X, will set you back nearly £1,000. Do be aware that all of Intel’s processor offer onboard graphics, albeit with weak 3D performance, while the Ryzen range has no graphics on its desktop range, so a graphics card is required.
Storage
There’s very little reason not to consider using a solid state disk (SSD) as your OS drive. It doesn’t need to be huge: an entry-level 240GB SATA drive will set you back around £90 and avail you of transfer speeds in the 500MB/s ballpark. For more serious speeds, you’ll want to bypass the SATA interface (and its paltry 6GB/s bandwidth) and go straight to the PCIe bus with an m.2 connector. This can boost your random reads up to around 2GB/s, with writes generally being about half of this. Larger capacities will see even faster rates, and with prices falling, 500GB is fast becoming the sweet spot here. Samsung’s 960 PRO offering will set you back around £270. Spinning rust still has its place though, and has never been more affordable. For this guide we’re recommending a twodrive RAID1 (mirroring) setup, which will save your data (and possibly you) in the event one drive ceases to be. Contrary to what you might suspect, buying two identical drives isn’t the best strategy here: there’s a minutely slim possibility they’ll have come from the same bad batch and have a common fault. Highly capacious, but slower drives, for example Western Digital’s Red series (aimed at NAS boxes) are becoming popular, and are fine for storing large files that don’t need to move around fast, such as media. You can get a 4TB 5,400rpm monster for £110, or if you prefer speed over space go for a 7,200rpm 3TB unit, which will set you back around £80. We’ll show you how to use bcache to speed up access to frequently used data.
Graphics cards
If you’re not planning on gaming, video editing or extreme number-crunching then you can go GPU-less on Intel systems – Ryzen APUs with onboard graphics are expected later in 2018. Entry-level discrete cards are cheap and much more performant than the integrated graphics in Intel CPUs, so you can always grab one after the fact. If you’re ardent in your support of FOSS you’ll probably want to go AMD here: its AMDGPU driver offers gaming performance on a par with Windows on selected titles/cards. Until Kernel 4.15 finds its way into your distro though, you’ll require a patched kernel (or the use of the proprietary AMDGPU PRO driver) in order to use HDMI audio or DisplayPort on AMD cards. High-end AMD cards (the RX400, 500 and Vega series) are in short supply thanks to the current altcoin mining boom. Newer Nvidia cards require signed firmware to work at full pelt, so the proprietary driver is your only option if you want to capitalise here. On the other hand, high-end games on Linux tend to do better with Nvidia hardware, but this will change.