## Archive for November, 2008

### OEM laptop has max CPU frequency capped when on battery

I was playing with a laptop from HP the last couple of days and noticed that when off AC power (on battery), the maximum CPU frequency is only half of the specification. The machine runs Windows Vista. The CPU is an AMD ZM-80, duo core 2.1GHz. On AC power, the processor can reach 2.1GHz on heavy load, but on battery power, the maximum it will go to is 1.05GHz on each core. This is really a problem because performance (especially for single-threaded applications) is pitiful at those levels. In fact, 1080p HD WMV demo videos could not play smoothly just like on a four-year-old Pentium M 1.6GHz.

### uniform by three

Here is a problem recently described to me. Apparently there is a more elegant solution (which may give more insight), but I don’t see it yet.

The problem: $$X, Y, Z$$ are independent random variables uniformly distributed over [0,1]. What is the distribution of $$(XY)^Z$$?

### bonus outrage, price transparency

GS chief gives up bonus for now… Some more discussion here and here.

Here is a money quote (pun intended):

There are instances where bonuses are justified, deserved, and in the best interests of the investment bank involved. Your very best people are people you want to hold, and your very best people will have opportunities even in this environment to transfer allegiance.

So the rationale behind the pay structure, allegedly, is to use the bonus as a kind of bribe money, to keep proprietary information (some term it “talent”, laugh) locked up within one firm. So in a way, bonuses have gotten far away from being a performance incentive.

### learning to use other senses (part 2)

… and squint.

This is part of the laptop backlight repair documentation.

So I gave up on fixing the laptop screen. The screen shall forever stay apart from the laptop. I even removed the laptop cover from its hinges so I just get a nice flat machine, and lighter, too. On second thought, this isn’t that bad. It’s no worse than a desktop machine. It’s still portable, and I just need to find a VGA monitor to connect to. Or just use Remote Desktop to connect in. Fine with me. But before I can get an external monitor, I still have a transition period where I need output from the machine right on the desk.

### one thing fixed (part 1)

… another thing breaks.

This is part of the laptop backlight repair documentation.

The main difficulty in replacing the CCFL is taking apart the laptop screen. I followed some of these references:

• This from here on how to open the lid portion that holds the screen.
• This from here on how to go the rest of the way to take apart the screen.

I didn’t take great pictures of the process but I took some.