uhm,

BF3 resource hunger
for desktop you already need:
at least Quad Cores (2.0ghz above)
at least 4GB or above
at least GTX 560 (for low->medium and smooth enough gameplay)
these spec consider as the minimum requirement for desktop

so for laptops, mobile versions spec, you need much stronger than these
mostly high end laptops that gonna cost you at least rm 4k above