speedstep issue with a twist

I have a

Dell e1705 laptop
Mobile C2D 2.0 ghz T7200
Intel 945GM chipset
2 Gig ram 667
500 gig HD
Windows 7 RC 7100

Weird problem. I was wondering why my WEI cpu score was an abysmal 2.6. So I fired up cpu-z and prime95 and guess what? The multiplier was locked at 6x leaving me running at 1 ghz. Even with prime95 running, there's no increase in cpu multiplier. So I checked my speed step bios settings. There are only two options. Turn it off completely and force the cpu into its lowest state which is 6x multiplier or have it turned on, which I already had. Then I checked power management options and made sure I was on high performance settings. I checked the advanced power management settings and put min and max cpu to 100% and still nothing worked. So I figured maybe speedstep just doesn't work in win 7. Now here's the real kicker. All of this was happening when I had the laptop plugged in! When I pulled the plug and ran on battery power, speed step worked like a charm and my cpu can go back to full blast at 12x multiplier and 2.0 ghz clock when running prime95. I really don't know what's wrong because I have identical settings for battery power and plugged in modes. Apparently, windows 7 just disables speed step when the laptop is plugged in, forcing my cpu into the lowest state. That's the opposite of what I want! Any ideas?

That sounds rather odd, not sure about this one.

Did you try creating a new power profile and using that one? Also did you check your CPU temps and make sure the CPU wasn't underclocking due to heat issues?

Nevermind. I figured it out.

It has nothing to do with windows 7 or the bios. What happened was I bought a new battery cuz my old one died. This new battery requires a 90 w AC adapter instead of the default 65 w AC adapter that came with my old battery. By not using the correct adapter, the system automatically forces the cpu into its lowest state.

Well, that was a good thing to know.

Glad you figured it out. Usually a laptop just won't power on if the AC adapter is the wrong size... it sounds like Dell skimped out on the charger since you originally ordered the machine with a smaller battery.