Valve's Timur Kristóf Got a 14-Year-Old Radeon HD 7870 XT Working on Linux

Timur Kristóf, an engineer on Valve's Linux graphics driver team, has been reworking Linux support for AMD's oldest GCN graphics cards, and one patch series made a Radeon HD 7870 XT work on open-source drivers for the first time, nearly 14 years after it shipped. The work was a lead item on Hacker News on October 4, 2026, where it drew 452 points.

The specific fix, reported by Phoronix on April 19, 2026, covers a Sapphire HD 7870 XT based on the "Tahiti LE" chip. That card was cut down from a premium part with part of its TCC cache fused off, a "harvested" configuration the amdgpu kernel driver did not handle. Bug reports for the failure date to 2013 and 2023. Kristóf began investigating within the previous six months, per Phoronix.

The HD 7970 above is a Tahiti-family card, the same generation as the 7870 XT.

Which kernel changed what

A Hardware Busters summary dated October 4 lays out the sequence. Phoronix's own reporting, which that piece cites, supplies the 30% figure.

Kernel	Change	Hardware
Linux 6.19	amdgpu becomes the default driver	GCN 1.0 (Southern Islands) and GCN 1.1 (Sea Islands)
Linux 7.1	amdgpu becomes the default driver	Kaveri APUs
Linux 7.3	Format modifiers and soft reset added	the same older cards

Hardware Busters names Tahiti, Pitcairn, Cape Verde, Oland and Hainan on the GCN 1.0 side and Hawaii and Bonaire on GCN 1.1. Examples include the Radeon HD 7970, R9 290, R7 250 and R9 280X. The move gives these cards Vulkan 1.3 through the RADV driver, DisplayPort MST, atomic modesetting and HDR, plus VCE1 video encoding.

The 30% figure and what it leaves out

Hardware Busters quotes Phoronix: "roughly a 30 percent performance uplift on these cards from the driver change alone" when the 6.19 switch landed. The test conditions, games, resolution and which cards were measured are not given in the Hardware Busters piece. A reader should treat it as a headline number from one outlet, measured against the legacy Radeon kernel driver, which is an old baseline.

The soft reset matters more for desktop users than the speed. Per Hardware Busters, a hung GPU no longer needs a full system reset.

What Kristóf said he would do next

On January 1, 2026, Phoronix published his plan for the year. It lists DRM format modifiers for SI, CIK, VI and Polaris GPUs to allow purely Vulkan-based compositors and Zink, display bridge support for CIK APUs, refactored power management for SI and KV, and retirement of the legacy non-DC display code. Bug fixes include a power limit issue on the Radeon 430 and display problems with analog connectors. A transfer queue for older GPUs in RADV is also on the list.

Format modifiers and soft reset arrived in 7.3 per Hardware Busters, so part of that list has shipped. The rest is unverified here: we could not confirm which items have landed.

What this does and does not buy

This is a support story, not a performance one. Cards from 2012 and 2013 do not become competitive; they stop being stranded. For a distro maintainer, it means one kernel driver rather than two for a decade-old install base. Our piece on Linux on the M4 Mac mini covers the opposite problem, new silicon with no upstream support, and our Rust Cargo metadata piece is another systems-software item from the same week.

What would change my read: a controlled benchmark of the 30% claim on named cards, and the kernel version in which the HD 7870 XT patches landed, which Phoronix's April piece does not state.