Given how WiFi is subject to interference and locations can fail and other machine continue on you find folk beating the bushes for answers.
Tell more about your monthly or bi-monthly maintenance such as the canned air on the vents.
Using my Acer 5610 laptop and a wireless-g linksys broadband router, my online access goes off intermittently causing me to have to disconnect, the reconnect again.
When I see the connection it shows only one or two bars, then when I re-connect all the bars are OK. And I run for another little while (sometimes as little as 15 minutes, and sometimes well over an hour or more).
Now the weird thing is I also run 2 other computers on the same router (but not at the same time), and I never have a problem with the other computers, even though I run the 2 other laptops at the same time, so I don't see how the problem can be traced back to the router or the internet access.
For further information, on the laptop I'm having a problem with, I run almost exclusively videos - mainly Netflix.
Thanks of any help.