What motherboard do i have with an acer aspire one 532h

It's a netbook, there ain't much that can be done with it. You can try using a single stick of 2GB RAM (DDR2 667 MHz SDRAM, soDIMM slot: Supports 1 GB soDIMMs for total system memory of up to 2 GB (up to 1GB for XP home models)) and see if it works, if not, then you either have to live with it.
There are somethings that you just can't do with portable stuff.
I'd advise you to buy a new netbook with highers spec, since changing anything in this one is going to work out equally expensive.