You could keep the PC on all
You could keep the PC on all the time (allowing it to only go to “away” mode), by disabling sleep (see power options). Another option would be to host the Ceton card in a server machine that is always on, but as you’re just “getting your feet wet” you probably don’t have that situation.
Unfortunately, the wait after power cycle of the Ceton card has something to do with authorizing the cablecard (perhaps some signal has to come down from the cable co) and the only way is to keep the power applied. HDHR Prime gets around this by having the unit powered all the time.
We tend to fire up the HTPC to watch pre-recorded content about 95% of the time, so it is not a big deal to wait for a bit on wake-from-sleep for live tv. For the first year, I didn’t allow my HTPC to sleep, as I was fearful about the WAF of the Ceton wait, and the reality of it is these machines don’t draw a lot of power (idling at 30w at $0.10/kwh or so… costs what… under $30 per year… assuming my math is right).