It really depends on your GPU drivers.
If you're using nvidia like 75% of Steam's hardware survey reports, it's a mixed bag and 1% lows are fucking abysmal compared to windows.
But try getting nvidia to care about Linux beyond CUDA. They'd rather just stop selling GPUs to normal people before they do that.
They're in the gradual process of open-sourcing their driver stack by moving the bits they want to keep proprietary into the firmware and hardware, much like AMD did many years ago.
It takes a long time to become mature, but it's a good strategy. NVIDIA GPUs will probably have pretty usable open-source community drivers in 5 years or so.