To find out what memory you have onboard and also where it is, here is a neat command
lshw -class memory
Here is my output
*-firmware description: BIOS vendor: Acer physical id: 0 version: V2.04 (01/15/07) size: 103KiB capabilities: isa pci pcmcia pnp apm upgrade shadowing escd cdboot acpi usb agp biosbootspecification *-cache:0 description: L1 cache physical id: 5 slot: L1 Cache size: 16KiB capacity: 16KiB capabilities: asynchronous internal write-back *-cache:1 description: L2 cache physical id: 6 slot: L2 Cache size: 4MiB capabilities: burst external write-back *-memory description: System Memory physical id: 12 slot: System board or motherboard size: 2GiB *-bank:0 description: SODIMM Synchronous physical id: 0 slot: M1 size: 1GiB width: 32 bits *-bank:1 description: SODIMM Synchronous physical id: 1 slot: M2 size: 1GiB width: 32 bits
I basically have 2GiB of memory and also L1 cache (on die cache on the cpu) of 16KiB and 4MiB L2 Cache.
Here is a wiki page that details what L1 and L2 cache are CPU cache, basically L1 means on CPU die, and L2 means slightly further away from the L1 cache. If there is a memory call L1 is the first hit, then L2 and then the memory and then swap space (harddrive), the lower down the line means slower result time.