Intel Power Boost without Simultaneous Multi-threading on i7

[odielag]

Hello. I have a dedicated server in a server farm and it's main purpose is to host a single instance of minecraft-server (game server). minecraft-server takes up one core.

I believe I disabled Hyperthreading in the bios by disabling "Simultaneous Multi-threading" and now instead of showing the 8 virtual cores in htop (system monitor) it shows 4.

So, it seems I was successful at disabling hyperthreading (and hopefully boosting performance).

The question now, is Intel Power Boost enabled? Power boost increases core clocks depending on temperatures and how much load in on how many cores.

I have heard it boosting a core to up to 4ghz, which would be great for the computer as it only really uses one core.

The problem is that I ran "openssl speed" to load a core, and indeed it did, but when checking the /proc/cpuinfo file it showed most cores at 1.6ghz and the loaded core at 2.8ghz (not 4ghz of speed boost).

So...

Is Power Boost enabled? If so, how can I tell?

Server info:
Core i7-930 cpu
OS: CentOS5.5 64bit

[vezhlys]

Core i7-930 can't boost core speed to 4GHz. It also doesn't change cpu speed only to one core. This feature is possible on socket 1156 and 1155 i7 CPUs. Turbo boost on this cpu can only increase your speed to 3.06GHz for all cores. I don't remember if you need HT and/or load all cores. You need to check BIOS options if this feature enabled or not.

[gshv]

I believe 3.06 GHz is the maximum turbo frequency for one core. Maximum frequency for two cores is 2.93 GHz.

Gennadiy

[vezhlys]

You might be right, I don't have nehalem system any more. One article about setting it up in BIOS: http://www.maximumpc.com/article/features/everything_you_need_know_about_nehalems_turbo_mode. Linux may need some additional tweaking in BIOS with power states.