If your Shiro modem (that pathetically unstable thing given by the wise folks at PTCL) restarts whenever there is a slight voltage fluctuation (or when the voltage goes low), get a new 9V 1A power adapter. I got one from Hafeez Center today for 200/- and it does wonders to my totally unstable modem when load shedding causes the UPS to kick in. (And no, I will NOT clean my modem!)