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Linux: AMD Phenom II and AMD Athlon II CPU Change Frequency On All Logical Cores

I've AMD Athlon II processors based server and it does not change frequency on all logical cores under CentOS version 5.5 or RHEL Linux. How do I fix this problem?
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Upgrade FreeBSD 7.x to 7.2 Stable Release

I tried a binary upgrade method, but it failed due to custom kernel installed on my FreeBSD 7.1_p5 64 bit AMD systems. How do I upgrade my FreeBSD server using source code method?
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Why does Linux top command shows two CPU when I have only one processor?

Q. I’m using CentOS Linux. I only have one processor (AMD 170 CPU) in my system, why does top command output report two processors?

A. You have a DUAL core CPU. A dual-core CPU combines two independent processors and their respective caches and cache controllers onto a single silicon chip, or integrated circuit. Some Intel P4 system comes with hyperthreading (HT) built into it.

This is not an error, it is a normal result of the hyperthreading and dual core CPU technology. This will improve system performance and will not harm any way to your server.

Various dual-core CPUs are being developed by companies such as Motorola, Intel and AMD. Following is the diagram of an Intel Core 2 dual core processor, with CPU-local Level 1 caches, and a shared, on-die Level 2 cache:
Why does top command shows two CPU when I have only one processor?
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