I am trying to upgrade my laptop memory from 256 to 1gb.

The current memory is a 256 MB PC2100 DDR SDRAM card.
I bought Kingston 512MB 200-Pin DDR SO-DIMM DDR 333 (PC 2700) to upgrade it.

I was just wondering my laptop would support it. I have seen two different things. One site says it does support the PC 2700 and one site says it does not.

Can anyone help tell me if it would work with my laptop?

Short answer: If it fits in the RAM slots it will work.

Long answer:It might not run at the fastest speed that the PC2700 can support, but it should run at the fastest speed the motherboard supports. I am assuming the form factors are the same.

thank you, just wanted to make sure it wouldnt fry my motherboard or something.

To be definite for you, PC2100 and PC2700 SODIMM have the same form factor.

So long as you are not trying to replace the 184 pin SODIMM version with 200 pin (i.e. you are replacing 200 pin PC2100) then it'll work fine.