That what is exactly I have been experiencing too. Our internet is not that strong sometimes because the weather will play up and keep changing, especially when its windy day. But, even though the weather is good,our internet is strong but then some website will take time to load,this is mainly because of viruses. So,I always clear my browser and use my Norton anti-virus to scan anything that the reason behind these lagging. Sometime, my Norton will detect from the website and it automatically repair it sometimes it will successfully repair,there are times,not. So maybe it is because some website that has virus in it,that made our browsing to load up.I don't know else what to do with this but,I asked some one who is computer savvy, and he told me that it might be the HDD that is not good enough to run the computer. Might need to change the HDD or buy a new computer.