How to make dash load faster in unity-2d

My dash always takes 10-15 seconds to show up. Is there a way to make it stay permanently loaded in the RAM or something so that it shows up faster?

Yes, this is Ubuntu 11.10. I have an old computer, so maybe that's the problem. My processor is Intel® Pentium(R) 4 CPU 1.50GHz and my graphics card is GeForce2 MX/AGP/SSE2

I think you are correct -- the problem is your CPU is old and very slow and your GPU (graphics card) is also old and doesn't support compositing and other features. This means everything must be rendered in software, and that is a burden for your CPU.

The Pentium 4 CPUs were notorious for providing extremely poor performance compared to what their clock speed was (1.5 GHz, here); for example, the CPUMark below shows that a Celeron M at half-the-speed or 800 MHz (released 3 years later) is faster than a Pentium 4 1.5 GHz:

Unfortunately, the solution to continue using the latest Ubuntu on your current hardware probably involves switching from Unity 2D to a lighter desktop environment such as XFCE or LXDE; perhaps you could try an Xubuntu/Lubuntu LiveCD to get a feel for what kind of performance to expect.

I really don't know if it will make your Dash open faster as this program makes programs lauch faster and the Dash isn't exactly a program, but you can test it:

sudo apt-get install preload

Preload is a little program that fills your RAM memory with the most used programs/files, so it won't work at the moment of the installation, but within two days using the pc it will take effect as it will memorize the common programs that you use.

Try

sudo dpkg-reconfigure unity-2d

and see if that speeds it up.