After 3 years of perfect use my laptop suddenly and without warning will lose all its free RAM and subsequently crash. This only happens if I access the internet. It still works fine until I go online. I have run virus and spyware checks with no positive results. I have run a self diagnostic and everything, including memory, checks out fine. Can anyone tell me what is happening and why. My laptop is a Dell Inspiron 9400 with 1gig of memory. It usually has 346Mb RAM free after booting, which as I said disappears within seconds. Any suggestions please.

It may be that you need to clean your computer. Even with perfect use, you may have dust buildup. Personally, I have little experience with Dells, but if you can provide a bit more info, then I may be able to help. I don't know if your computer can, but if your computer is compatible with ReadyBoost, then stick in a 1-2GB flash drive and use ReadyBoost with it. A 1-2GB external RAM can't hurt.

You might have too many applications running at start up. Check the startup folder and also how many applications are you running.