Over the course of about 1 year, my network troubles went from slight lapses in connection (enough to stop a download, but nothing long or serious), to extremely unreliable speed and frequent, serious connection failures. I have just replaced a Linksys Wireless B router with a Wireless B/G router, though I am only using the B functionality. Since the replacement, my connection has just been very slow randomly, but often - only when I try to play an online game does the connection totally give way (even after playing around with DMZ routing and disabling the firewall).
Any suggestions would be greatly appreciated.

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