Your system information

• Steam client version (build number or date): 2018-06-01 10:51:49
• Distribution (e.g. Ubuntu): Arch Linux
• Graphics driver version (run nvidia-settings): 396.24
• Gist for SteamVR System Information: https://gist.github.com/fahrstuhl/d31f7ccfd26ec4b4652d1092511bfcaf
• Opted into Steam client beta?: Yes
• Opted into SteamVR beta?: Yes
• Have you checked for system updates?: Yes

Please describe your issue in as much detail as possible:

Steam VR does not start correctly and throws error (301): "A key component of SteamVR isn't working properly."

dmesg -T reveals an invalid opcode in driver_lighthouse.so:

[Di Jun 19 14:10:18 2018] traps: Connection - vr[8085] trap invalid opcode ip:7fa5fe6d4abc sp:7fa5ff417370 error:0 in driver_lighthouse.so[7fa5fe639000+26e000]`
[Di Jun 19 14:10:27 2018] traps: Connection - vr[8250] trap invalid opcode ip:7f60395beabc sp:7f603a301370 error:0 in driver_lighthouse.so[7f6039523000+26e000]

My CPU is an AMD Phenom II X6, which does not support the SSSE3 extension. My issue is probably similar to #26.

Steps for reproducing this issue:

1. Start SteamVR on AMD Phenom II X6 CPU