Yes it supports up to 8 gb. When you do get more try and get the same memory you are using now but in 4 gb sticks.
2 x 1.5V DDR3 DIMM sockets supporting up to 8 GB of system memory
* Due to Windows 32-bit operating system limitation, when more than 4 GB of physical memory is installed, the actual memory size displayed will be less than 4 GB.
Dual channel memory architecture
Support for DDR3 1333 (O.C.)/1066/800 MHz memory modules
(Please refer "Memory Support List" for more information.)