Mixing memory speeds

Currently on my crap-box (rebuilding this month or the next), I have 2 128MB sticks of PC100 RAM. Someone bought me a 128MB stick of PC133 ram. I have them all installed and I was wondering if mixing these two speeds will actually do more harm than good.

the Ram will run at the speed of the slowest module you have.. in this case the PC100
theres nothing wrong with it

snipester said it. i would just sooner get ddr ram, i will never go back to sdram.

ahh, ok. Thank you very much. I'm getting DDR in a few weeks when I buy the components for my new system.