I have a Motorola Surfboard modem. When there's a power outage or I just want to re-set the modem, when it boots up, it gets to the PC Activity light (circled in red in the photo), blinks around 30 times, then all the lights go off, then it starts booting up again. The second time it boots completely. Is this normal or more likely a problem with the modem, my computer, or the signal?
Note that the SB6121 is technically obsolete. It only has four downlink channels and therefore doesn't bond properly above 60 Mbps. You need a minimum of 8 DS channels (SB6141) to get a 100 Mbps connection, 16 for up to 300, and 24 for the ultra 400 Mbps.
Will that modem work with Windows 7?
What modem are you referring to? The short answer is Yes since modems don't really care what operating system is being used.
I feel like you may really be asking a different question...something like "What modem should I get to optimize my connection?" perhaps...