Dunoonian

Right well, I am having problems running attack of the B-team. (My PC specs are below) when I click "Create new world" it generates like any normal minecraft world but when it is supposed to load in it says "Minecraft ran out of memory" now I don't have much RAM anyway but when I try to allocate more RAM to technic altogether it only allows a max of 1GB. so I ask, how do I give my modpacks more memory? My Specs: Operating System: Windows 8 64-bit CPU: Intel Pentium G2020 @ 2.90GHz 30 °C Ivy Bridge 22nm Technology RAM: 4.00GB Single-Channel DDR3 @ 665MHz (9-9-9-24) Motherboard: Packard Bell imedia S2870 (SOCKET 0) 28 °C Graphics: DELL E228WFP (1680x1050@59Hz) Intel HD Graphics (Acer Incorporated [ALI]) Storage: 465GB Seagate ST500DM002-1BD142 (SATA) 42 °C Optical Drives: HL-DT-ST DVDRAM GH82N Audio: Realtek High Definition Audio (I know that most of that is extra information but I copied it over from speccy)