Why it is slower?

There are few possible reasons:
1. You feel cramped using a small device compared to a PC. So <i>psychologically</i> you fell slower because you work uncomfortably?
2. Overall system performance depends not only the processor speed; RAM, HDD, GPU etc contributes to that.
3. What else? I dunno.

Smart guys are not smart; they only see things in different perspective.
1st <b>ENTHUSIAST</b>!

Notebooks are smaller with heat dissipation problems and so they use slower bus speeds to keep temps down. Even though a desktop 400MHz system is using a 100MHz bus, the notebook will still be using a 66 or even lower bus speed and that makes a huge difference. Also, you may have an ATA/33 or higher hard drive while the laptop still uses the old EIDE at 16MHz.

James

First off the PCMCIA interface isn't as fast as newer IDE interfaces (DMA66/DMA100) and that is probably slowing you down some, second check memory speed and amount, that contributes, third check on graphics card, it might have shared memory and it very likely is subpar to the one in the desktop system. And lastly modern laptops will underclock the processor in order to conserve power. Your laptop is probably doing this whenever you aren't using extremely CPU intensive tasks, thereby slowing down the responsiveness of windows and other applications.
I suspect that last point is the real culprit but the other factors do make a difference. Sometimes you can turn off this power conservation feature, check around windows power management and bios settings, it may be an option if you are willing to sacrifice battery time for clockspeed.


-Infornography
life as we know it is absurd

I've noticed that motherboards can have a drastic effect on performance. That's why I really can't wait for Intel to make a DDR motherboard. I'd rather wait for that than to rely on a VIA DDR motherboard.

I recently paid almost nothing for a Celeron 500 using a BX motherboard. I was telling a cousin of mine how it was running Frodo (a C=64 emulator) at over 800% speed, which was phenominally better than my old P1-133. He was astounded by this, because his 100MHz FSB P3-600 in a VIA chipset was only getting between 500% and 600% speed in Frodo. Granted, he's been having problems with that motherboard from day one. Which is why I just plain don't trust VIA, after helping diagnose and solve all of the problems he's had with memory and AGP video cards (3dfx Vodoo 2 and 3)that according to VIA tech support 'don't conform to standards' when they all run perfectly fine in his old P2-400 system on a BX motherboard.

Needless to say, our next project will be putting the 600 on the BX motherboard. Heh heh.

- Anything can be fixed with duct tape, a swiss army knife, and WD-40.