Bug 263786

Good morning,
I bought this computer => https://electrotounes.tn/pc-portable-dell-vostro-3500-i3-1115g4-4go-256go.html  
 but I have a problem with this computer which is getting heavier and heavier
I've formatted it several times but the first few days it works well but after everything goes back to how it was before
I added another RAM but no way so I changed Xp another time it was always the same result
I tell you that it becomes even louder when I link to some website, like caramail for example, the page remains for a few minutes and after that it blocks permanently, and when I close the page a message appears asking me to report it 'error
in addition the majority of internet pass when the display ends I find a message in the status bar write: "Completed, but there are errors on the page"
even with internet 7 it's the same thing, even more worse
so,
is it possible to make my pc faster?
is it possible to eliminate all errors on web pages?
Thank you for your reply