Low fps in lol client

so i have a dell laptop with proccesor Intel(R) Core(TM) Duo CPU P800 2.53GHz 2.54 GHz 64 bits with 4 Gb ram from the 9.20 patch my client started laggin very hard in the point i cant enter a match bcs it doesnt load and it slow my laptop as well and idk waht to do adn pls dont judge me, i cant afford a new one to soon bcs i barely have money but thats not important, i have this laptop for almost a year and it worked dencent but now its really slow maybe u guys can help me