|We really need your system specs but I can give you some generic advice.|
The AXP 2000+ stock clock settings are 12.5 x 133MHz (1.67GHz). The multiplier is probably locked at 12.5x so all you'll be able to do is increase the CPU frequency. A few important things you need to know:
1.) all socket A systems perform best when the CPU & RAM run at the same frequency, this is known as 1:1 ratio. If the CPU is at 133MHz, the RAM should be at 133MHz. If it's at 140MHz, the RAM should be at 140MHz, & so on.
2.) when you increase the CPU frequency, all other frequencies (RAM, PCI, AGP, IDE) will also increase unless the BIOS provides a setting to lock them. If no lock is provided, you have to be very careful to keep the affected frequencies within acceptable tolerances.
3.) the AGP frequency is always 2x the PCI frequency. The stock PCI freq is 33.33MHz, therefore the stock AGP freq is 66.66MHz. There is no real advantage to increasing these freqs, but if they are increased too much, they will cause system instability, problems with the audio, data corruption on the HDD, etc. Generally, the max safe PCI freq is 37.5MHz, therefore the max safe AGP freq is 75MHz.
4.) if there is no way lock the affected freqs, the max safe CPU freq is 150MHz unless you can bump up to the next standard CPU freq of 166MHz.
I do not recommend running Win7 on this system. It's too old & you have too little RAM. And my guess is you're still running the onboard video.