Any black box computer geeks out there?

My Dell computer which is now going on 8 years, is doing crazy stuff. I cant tell if its starting to fail or not. Its making a lot of noise & I guess thats the Hdrive. More times than not it will click away like a 50 cal. machine gun on top of Pork Chop Hill. While its doing that, I can use the computer but it it will take forever to load a website, bring in the email, etc. I will sit here with that stupid hour glass thingie. Its like it just stalls. Sometimes this will go on for a half hour to hour and a half. Then when the stupid thing finally quiets down, it runs fine. Im also running Nortons 360 & I think it is constantly loading security stuff or causing a problem. Not sure how to turn it off to see if it makes a difference. And then Im not sure on how to get it back on. Its a Dell & its running with no longer supported XP. The most recent repairs to it was over a year ago, where my computer repair shop had to replace several Condensers (I think) off the mother board because would not fire up one day. They showed me the parts they replaced for about $100.

Also, Im on a wireless internet service & it tells me they are at 65 MBPS & signal strenght is excellent.
I think Im due for a new computer after almost 8 years. BUt before I buy one Im trying to determine if I really do have a machine issue & not an internet issue. Is there any way I can tell for sure whats going on other than throwing it into the shop & asking them to check it out. Don't know much about this high tech. junk. Looked inside it one time & could not find any fuel injectors, pumps, oil sumps, air filters, or fan belts. Put the cover back on & said to myself....screw this. :empathy: