In brief: The Steam Machine's software is fully customizable, allowing users to install non-Steam apps and even different operating systems. However, the living-room PC's locked-down hardware is far from high-end, an issue some users have addressed with ambitious modifications.
Two recent modding projects aim to substantially boost the Steam Machine's performance. One modder discovered a roundabout method of adding external graphics, while another built a water block from scratch to achieve dramatically lower temperatures.
Valve's Linux PC offers a comfortable living-room experience with a controller-friendly interface and a tiny form factor, but its 8GB RDNA 3-based graphics card struggles with high-end games, especially on 4K TVs. Most other desktop PCs would allow users to resolve the issue via upgrades, but the Steam Machine's unique chassis makes this significantly more complicated.
For example, many likely wish that Valve had included external graphics support out of the box. Handheld PCs from other manufacturers can be docked into high-end desktop graphics cards via USB4, OCuLink, or Thunderbolt 5 ports, none of which the Steam Machine includes.
However, Redditor "Large_Customer_3840" successfully connected an AMD Radeon RX 9070 XT to the device by running its M.2 drive through an OCuLink adapter. Since the Steam Machine's sole M.2 drive manages the system's boot storage, he had to reroute the NVMe SSD through a USB-C adapter.
While the process introduces some quirks, Large_Customer claims that the PC booted up immediately. The new GPU ran Crimson Desert at between 40 and 100fps on high settings at 1440p, though there were audio glitches, likely related to SSD bandwidth. The modder recommends that anyone else interested in repeating the process seek an NVMe enclosure with active cooling and at least 40Gbps of bandwidth.
Meanwhile, a recent video (above) from German YouTuber Techmagnet outlines how to completely disassemble the Steam Machine and insert a custom-built water block. A subsequent video on Reddit shows the construction of the water block using 3D-printed components.
While the process leaves large tubes protruding from the Steam Machine, Techmagnet claims it lowers temperatures by 20 to 30 degrees Celsius. However, using the extra headroom for overclocking would require a custom BIOS. With additional work, water cooling the SSD might also be possible.
Ultimately, the Steam Machine's biggest weakness is its price, which starts at $1,049 due to soaring memory costs. While the RAM crisis has affected virtually every hardware manufacturer, Valve was particularly vulnerable due to its relatively small presence in the hardware market. Still, the company is selling as many Steam Machines as it can build, and new orders are currently waitlisted.