I’m Using Windows Vista & its Very Slow Especially When I Using the Internet…need Help How to Speed Up my Pc?

I have a HP A1720, 3gb ram, 320gb harddrive, windows visa 32bit, intel core 2 processor 6300 @ 1.87mhz. i did almost everything i can think of such as, ran registry cleaner , ad-ware, spyware, spy bot, norton anti virus, did a disc clean, disc defragmentation with no help in the pc speed on the internet i hav a high speed internet provided i dont have too many icon on the desktop either my pc performance base score is 2.8 processor sub score is 4.9 memory sub score is 5.2 gaming graphics

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