Will this ram work with my P5P800SE Asus motherboard?

I have a P5P800SE Asus with Apacer 512 UNB PC3200 CL2.5 (x2). I also
having lying around this RAM :
-Apacer 256 UNB PC 2700 CL2.5
-MEP 256 UNB 256 PC 2700 CL2.5
-and a stick of 512MB DDR 333

They all look the same in size and slot width. Is it ok to test these
without worrying about other RAM getting fried? I know the RAM works
in an older system, but I haven't tried it with this newer
motherboard. With this new RAM I am up to 2GIG, which would be nice.

Any ideas?