I'll try updating the bios, It's still at stock bios
I'm overclocking using the "Turbo in Bios" mode where you se each individual turbo setting.
Speedstep does work fine, but it's a bit confusing. For one thing, look in the cpu0/1/2/3 folder un the /system/cpu dir, those folders each have their own freq settings (for each core). Secondly, no matter what your overclock is, this is how the frequencies are listed:
3301 MHz- your turbo overclock
3300 MHz - 3.3 GHz
I've tested this myself, with the CPU set to 4.4 GHz in EFI linux still claims 3301 MHz, however benchmarks scores are 33% better than if I use speedstep to force the CPU to 3.3 GHz.
The cpu scaler has another bug, in that it doesn't correctly set scaling_min_freq. When I boot the CPU is stuck at 4.4 GHz because scaling_min_freq is 3301 MHz. If I manually set it too 1.6 GHz then the CPUu autoscaler will start working and the CPU will scale back to 1.6 GHz.