3DFX / Mesa passthrough

The WSH extensions bundle a QEMU build patched with qemu-3dfx, which passes 3D rendering through to the host. This enables hardware-accelerated 3D (Glide and OpenGL/Mesa) in old Windows guests via a set of guest-side wrapper drivers.

Caution

This is an experimental feature. It requires a matching pair of host QEMU and guest drivers — see version pairing below.

Version pairing

3DFX/Mesa passthrough has two halves that must be built from the same qemu-3dfx commit:

• Host — the pve-qemu-kvm package bundles the qemu-3dfx patch. The patched qemu-system-x86_64 binary embeds a short revision string (__REV__, the first 7 characters of the qemu-3dfx commit).
• Guest — the wrapper drivers installed inside Windows embed the same __REV__ string.

The wrapper refuses to load against a host binary with a different revision, so the two versions are locked together by design.

To find the matching pair:

1. Check the pve-qemu-kvm release notes — they state which qemu-3dfx commit the build was made against (for example qemu-3dfx-drivers-b47f30a).
2. Download the guest drivers from the releases page with the same short SHA — the release is tagged qemu-3dfx-drivers-<shortsha> and includes a VERSION.txt recording the full commit.

Enabling on the host

1. Set the guest Architecture to x86_64 (see Architecture).
2. Enable the 3DFX/Mesa option in the Display panel. When selected, the guest is started with the passthrough-patched qemu-system-x86_64-3dfx binary instead of the standard one.

Installing the guest drivers

Download qemu-3dfx-drivers-<shortsha>.zip from the releases page (matching your pve-qemu-kvm version). It extracts to a single folder containing the Glide and OpenGL/Mesa wrappers:

fxmemmap.vxd, fxptl.sys, glide.dll, glide2x.dll, glide2x.dxe, glide2x.ovl, glide3x.dll, glide3x.dxe, instdrv.exe, opengl32.dll, wglinfo.exe

Transfer the files into the guest and install the ones for your Windows version:

Windows 9x / ME

• Copy FXMEMMAP.VXD, GLIDE.DLL, GLIDE2X.DLL, and GLIDE3X.DLL to C:\WINDOWS\SYSTEM
• Copy GLIDE2X.OVL to C:\WINDOWS
• Copy OPENGL32.DLL into each game’s installation folder

Windows 2000 / XP

• Copy FXPTL.SYS to %SystemRoot%\system32\drivers
• Copy GLIDE.DLL, GLIDE2X.DLL, and GLIDE3X.DLL to %SystemRoot%\system32
• Run INSTDRV.EXE (requires Administrator privileges)
• Copy OPENGL32.DLL into each game’s installation folder

Further reading

• The qemu-3dfx project
• The Display reference for the graphics card and 3DFX/Mesa options