I think you will reach the limits of your processor before you reach the limits of even your cheap memory.
CPU-Z Memory tab
DDR2 2GB DRAM
FSB: DRAM 3:4
The only problem I see is the FSB:RAM ratio. Right now you are overclocking your RAM. As you push your FSB higher, you will exceed your RAM's capability.
In your BIOS, take the memory clock setting off Auto and select the 2.00 multiplier. You want the memory clock to be twice the FSB frequency.