mixing memory on kt133a and PIO/DMA questions

[alfhead]

Hello, I just put together my first rig today.. MSI K7t turbo (kt133a), TBird@1000, 256 pc133 cl2.
my first question is that I have an old stick of 128 pc100 ram from my last system.. can i use that along with my new pc133 ram? If I do, am I restricted to setting the FSB at most at 100? my other question is about my hard drives. I have one deskstar ata100 as the primary ide master and a maxtor udma 33 as the slave. in my bios should i set the pio modes to 4 or keep it at auto? what exactly is pio compared to dma? what should i set the udma settings to? I'm kinda clueless on the whole pio/udma thing so any info would help.

 

[ddiccico]

this board does 133 fsb right? forget about the pc100 ram, and use pc133 so you can run the fsb at 133+.

pio modes 3&4 are 16.6 MB/sec (if I remember correctly).

set the bios to auto, and they should be detected fine.
I think that you cannot mix modes on a bus though (someone correct me if I'm wrong), so they'll both run at the speed of the slowest device. put them on different buses for better performance.