Building the ultimate X99 gaming and benchmarking PC

There are all sorts of reasons why you might want to get into PC gaming over or in addition to a console. There’s the huge library of comparatively cheap games on Steam, the niche indie games that just wouldn’t find a home anywhere else, or maybe even the flexibility to run games on anything from lowly laptops all the way through to watercooled 4K behemoths.

All this possibility tends to create a rare breed of gamer, the ones who obsess over clock speeds, how much wattage their power supply puts out, and if you really can cram an 8-core processor and a Titan X into a PC the size of shoebox. Consider me one of those people. For me, picking out the right components and building it all into a sleek, cable-managed rig is as much a part of PC gaming as it is actually playing games.

The launch of Ars Technica UK was a prime opportunity to indulge such nerdisms. The site needed a brand new benchmarking PC, and building one was a far more enticing proposition than just buying an off-the-shelf Alienware or Digital Storm. While those companies (and others) make solid gaming rigs, what we needed was more flexibility than they would necessarily allow.

The PC had to have the power to play the latest games, of course, but we also needed easy access to components so that we could swap in new graphics cards, processors, SSDs, or whatever bit of shiny new tech needed to be put through Ars Technica benchmarking hell that week. That means the hardware choices for the Ars Technica UK PC might be a little different to what you’d typically choose to use at home, but hopefully illuminating the process will help inform your own builds.

Choosing the components

The CPU is usually the most sensible place to start a PC build, given that it informs other choices like the motherboard and the RAM. How much money you put into it largely depends on your priorities and budget. For example, if you’re building a PC for gaming, then you’ll want to reserve a good chunk of cash for a graphics card. The Ars UK PC isn’t just going to be used for gaming, but also for testing graphics cards and other bits of hardware. Ensuring that the CPU wasn’t a bottleneck for other components was a must.

For high-end builds, Intel is the only way to go. AMD’s CPUs are good if you’re on a budget, but until Zen appears—and the jury’s still out on when that might be—their single-threaded performance just can’t compete with Intel. From there, it’s a case of choosing between a Core i5 or i7 from the Devil’s Canyon range, Skylake, or Haswell-E. Devil’s Canyon is still a great platform, particularly as Skylake is only around 10 percent faster on average, but because it’s based on an older chipset, Devil’s Canyon lacks a few newer features.

The Skylake Z170 chipset adds DDR4 RAM and additional bandwidth to support more PCIe lanes: 16 PCIe lanes on the CPU and another 20 PCIe 3.0 lanes on the chipset, a big increase from the eight PCIe 2.0 lanes on previous chipsets. There’s also double the bandwidth between CPU and chipset thanks to DMI 3.0, as well as more USB 3.0 ports and support for NVMe SSDs over the chipset lanes. The problem, however, is that Skylake CPUs still currently top out at four cores with hyperthreading. That’s not a problem for playing most games, but there are certain benchmarking scenarios where having more cores available might be useful.

For instance, as Windows 10 adoption ramps up and DirectX 12 games follow, just how much of a difference do the extra cores make? With companies like AMD heavily promoting the multithreaded advantages of DX12, seeing what the future might hold for the API is important. Complex computational science tasks and 3D rendering applications, which are usually configured to take advantage of multithreaded CPUs, benefit greatly from more cores, too. So while it’s easy to disable cores on a multicore processor to simulate the performance of a mainstream four-core CPU like a Core i5, it’s impossible to add more. For deeper testing, Ars UK needed more cores.

That left us with Haswell-E, Intel’s high-end enthusiast platform. It not only features niceties such as support for DDR4 RAM and crazy-quick M.2 SSDs, but also six- and eight-core CPU options. The cheapest CPU, the £300 ($400) Core i7-5820K, is a great buy, especially if you’re considering Skylake at the moment. You’d get two extra cores, plus the same DDR4 goodness for nearly the same price. But while the i7-5820K has six cores, it only supports 28 PCIe lanes, which can create a bottleneck if multiple graphics cards and M.2 PCIe SSDs are placed in the system during testing. The eight-core i7-5960X on the other hand features 40 PCIe lanes, but it costs an eye-watering £800 ($1,100).

The sweet spot is the Core i7-5930K, which features six cores, 40 PCIe lanes, and runs at 3.5GHz, boosting up to 3.7GHz under load. While that’s less than the 4.4GHz boost of a Devil’s Canyon i7, it’s nothing that a little overclocking can’t fix. That said, if you decide to go for a Haswell-E setup, it features the highest thermal displacement of any Intel CPU—140W—so plan your power supply and cooling accordingly.

With the CPU chosen, the rest of the parts fell into place. For a motherboard, we settled on the £320 ($399) ASUS X99 Deluxe USB 3.1. It can handle up to four-way SLI/CrossFire and comes equipped with dual 32Gbps ultrafast M.2 x4 slots, SATA Express, 12 SATA ports, two Intel Gigabit NICs, support for up to 128GB of RAM, and a killer 8-phase digital VRM design for rock solid stability. You name it, this motherboard has it. 32GB of Corsair’s 2800MHz C16 Vengeance LPX RAM, spread across four 8GB sticks in a colour-matched black, takes care of memory, while a beefy Corsair H110i GT 280mm closed-loop liquid cooler takes care of dissipating the CPU’s ample TDP.

Why not a custom watercooling loop? While that would have provided superior cooling for the CPU and for GPUs, it wouldn’t have been as flexible. With graphics cards (and possibly CPUs and motherboards) needing to be swapped out for testing, a closed loop is far easier to disconnect, and it requires zero maintenance.

Choosing a storage solution, however, was a little more complex. Obviously, getting the fastest storage possible is a good idea, but not everyone will have something like a 512GB Samsung SM951 M.2 PCIe 3.0 SSD, which uses up four PCIe lanes for speeds of up to 2.2GB/sec read and 1.5GB/sec write. To help with testing on more common setups, the SM951 was paired with a 500GB Samsung EVO SSD (named the “the best consumer-grade SSD” by the Wirecutter), as well as a good ol’ 3TB 7200RPM Seagate hard drive. The monitor that you can see in the video is the (rather superb) ultra-wide 21:9 LG 34UC97; sadly, LG wanted it back shortly after we shot the video.

Power comes courtesy of a 1200W Corsair HX1200i complete with colour-matched sleeved white cables (chosen for the company’s renowned PSU reliability), which should provide more than enough juice for even the most over-the-top CrossFire or SLI setups. Other practical additions include a Blackmagic 4K video capture card for capturing console video footage, a 5.25-inch hot swap drive bay, and an LG Blu-ray drive, because, oddly enough, press still sometimes get sent things on a physical disc. Graphics (when not being swapped out for testing) are handled by an Nvidia GTX 980 Ti. While not technically the fastest GPU Nvidia makes—that’ll be the 12GB Titan X—it’s almost as fast, and costs nearly half the price at £550 ($650).

Finally, to house all that shiny tech, there’s Corsair’s Graphite Series 760T, a full-size tower measuring 564mm tall, 246mm wide, and 568mm deep. While that’s quite large for a PC (it’s bigger even than an old cheese grater Mac Pro), that space means that no matter how long the graphics card, how big the cooler, or how many drives need to be installed, it can handle it.

Oddly enough, settling on a case was actually one of the trickiest parts of the build. Aside from the fact that there are literally thousands of different PC cases to choose from, all with different aesthetics and internal configurations, there was also the question of whether an open test bench would be a better idea, given that components would need to be swapped out regularly. Unfortunately, test benches need desk space, and that’s not something that’s easy to come by in the Ars UK office. The 760T’s hinged side panels, which open fully via a handy lever, make getting inside easy. Its sheer size also means there’s plenty of room to work.

The total build cost, if you’re curious, was about £2,700 or $4,200—not including the monitor.

Putting it all together

Putting the PC together was a breeze, mostly thanks to the capaciousness of the case. With smaller cases you normally get as much as possible assembled before screwing things in—usually the CPU, RAM, and cooler, at least. But with the 760T it’s not really necessary. There’s a large CPU cut-out on the back of the motherboard for installing coolers—although, that wasn’t needed because of the LGA 2011-3 socket having integrated cooling standoffs—while the sheer amount of space inside meant that we didn’t encounter any tight fits. We did remove both the 3.5-inch drive cages from the bottom of the case. With the M.2 SSD sitting on the motherboard, the SATA SSD sitting in one the dedicated SSD sleds on the back of the motherboard, and the hard drive inside a hot-swap bay, they simply weren’t needed. Removing them gave the case a much cleaner look.

The one big issue we encountered was with the LG Blu-ray drive, which—thanks to its oddly shaped eject button—refused to work with the stealth drive bay of the 760T. We also had to add one of NZXT’s rather handy internal USB 2.0 header hubs in order to plug in the front panel headers, and the power supply and CPU cooler, both of which make use of Corsair Link for control via software. With nearly an inch of space around the back of the motherboard tray and rubber grommets surrounding the motherboard, managing cables with a few well-placed cable ties was easy. There was even plenty of space to add a few LED lighting strips just for that little extra bit of bling.

21:9 ultrawide displays are all the rage right now, but could be usurped by 32:9 in the future.

Performance

After going through the usual Windows 10 install process (using the M.2 SSD as the main boot drive), the first step to killer performance was to make up for the lower clock speed of Haswell-E with some overclocking. We won’t go into the full overclocking process here (Asus actually has a good guide), but suffice it to say, Asus’ UEFI BIOS and the stability of the board made it a very simple process. Under stock speeds, our CPU pulled around 1.050v, which needed bumping to 1.29v in order to remain stable at 4.5GHz. At full whack, CPU temps never climbed above 79 degrees Celsius, which is a great result for what is already one of the toastier Intel CPUs.

Once a stable voltage was established, it was back into the BIOS to enable XMP on the RAM, which bumped the clock to 3000MHz. From there, it was a case of adjusting the CPU multiplier to take into account the increased base clock speed of 125MHz set by the XMP profile, and changing from manual to offset voltage. The latter re-enabled the CPU’s power saving features, which dropped the voltage when the CPU wasn’t under load, helping to save power and reduce heat.

With six CPU cores running at 4.5GHz, 3000MHz DDR4 RAM, and an M.2 SSD under the hood, naturally the PC flew through benchmarks. While we didn’t run a full set of gaming benchmarks on the PC—mostly because you’ll be seeing a lot of them in the future anyway—we did run a few disk-based and CPU-based benchmarks to give you a rough idea of the sort of performance you can expect from such a setup. CrystalDiskMark showed peak sequential reads of 2185MB/sec and 1563MB/sec writes. With 4K loads, reads hit 580MB/sec and writes 389MB/sec, all of which are extremely impressive figures given most SATA SSDs top out at 500MB/sec under sequential load.