HTPC Log 01 – S3 Sleep, TV Tuner Quality
(Quick Specs: an old shuttle PC running Vista. ok, I can’t remember the specs. will update later)
Attempting to get S3 sleep state to work.
Had to change power settings in BIOS – ACPI Standby State set to S3. I think setting it to S1&S3 didn’t seem to work, will elaborate more on this later.
Initially, I followed the instructions as linked above but it made things worse – the PC didn’t seem to power down at all, with the “On” indicator light not going off. It turned off the TV display but that’s about it.
Then I found out that the problem was having created based off the High Performance plan. When using High Performance, the computer doesn’t sleep much, only as above. Switching to Power Saver fixed this, and my shuttle went off nice and quiet (previously you could still hear a fan spinning), as if it was completely off. Cool.
Minor problem at this point – had to push power button to wake it up, keyboard/remote control didn’t work. Fixed this by enabling wake by USB keyboard in BIOS.
Quick elaboration on setting BIOS ACPI Standby State to S1&S3 – when I had done so earlier, I think I was still using the High Performance plan. Don’t remember testing after I switched to Power Saver.
Next attempted to schedule a recording and put computer to sleep. However PC seemed to just turn off the display again. Suspecting Windows (Vista) Media Center to be preventing proper S3 sleep, closed VMC and tried going to sleep. Success. It came on as scheduled to record, but it didn’t go back to sleep after that.
End of this for today.
Noticed that watching TV through the PC (tuner card) was significantly worse than watching from Starhub HD STB. Understandable since what I’m getting is probably the analog free-to-air and signal strength is not as good as cable’s (and it’s analog vs. digital). Currently I’m using the TV OUT from the Starhub STB to connect to PC (via coax cable). Rerouted this TV OUT to TV to test signal quality. TV looks better than PC, but still worse than cable STB (over HDMI). Makes sense, but notes that the PC is indeed degrading quality. I need to figure out if it’s due to the TV card, or a VMC problem. Perhaps VMC is enconding the video badly before displaying? Or is the video encoding handled by the TV tuner card? The “bad” quality looks like it may be a compression issue. Will have to look into this.
Next up…
- Fix S3 Sleep
- Run another scheduled recording test, see if it goes back to sleep
- Verify scheduled recording behaviour by reverting to regular sleep
- Find out if this uses the Windows Task Scheduler. If so, might be able to get info from that.
- Verify inability to sleep when hybrid sleep enabled and VMC running
- Improve Live/Recorded TV Quality
- Check if it’s signal quality issue (including analog vs. digital) by switching to composite video input from STB (ie. see how cable channels look like)
