Two routers inexplicably died - do I need to start buying them in six packs?

First one was a Linksys BEFSR41. After an outage problem with my ISP,
we got the net connection working OK but the router could not be made
to work. I figured it was because I was doing port forwarding with it
before, but no amount of power cycling and reset buttoning would help.
Cable connection worked fine when the PC went right into the modem, as
soon as I put the router into the loop - nothing.

So I bought a Belkin F5D5231. Worked OK for 3-4 months. This morning
- nada. Again the connection is fine when the cable modem is plugged
into the PC, zip when I add the router.

I spent half an hour tonight swapping routers and cables and
resetting, all to no avail. All the lights are on where you would
expect, just no signal traveling through either router.

Do I have to start buying them by the case??