04-25-2010 07:52 PM - edited 04-25-2010 08:12 PM
Dear HP engineers
I have notice that there is high-frequency noise in my dv5 laptop. The noise is came from the CPU. Disable Processor C4 state (or disable CPU Power Management in BIOS) can solve this problem. I googled this problem, and found that many people can hear this kind of high-frequency noise (very different from HD or Fan noise) with different brand of laptops. They solve it by disabling CPU Power Management in BIOS. And this problem CANNOT be solve by changing Power Options in Windows.
However, there is no such Processor C4 state (or Processor Power Management) options in BIOS setting page. There is only Processor C6 states option. I disabled the C6 State but nothing happens, CPU power management still enabling by the BIOS.
If I let CPU work in high usage (such as run video convert), the noise will completely disappear. When the CPU in idle, noise appears again.
I'm already on the latest BIOS F.21 (dv5 / Intel Processors). The noise is really annoying me. I would prefer to hear noise from Hard Drive or Fan, but I don't want to hear the high-frequency noise from CPU.
I hope HP engineers could add Processor Power Management option in dv5 BIOS, as many of other brands have this function.