[mythtv-users] Hardware Supporting (resume from) Suspend to RAM

[Allan Stirling]

Ben Curtis wrote:
>> I can shut the frontend down with the remote (in this case an MCE unit),
>> but as yet I cannot get it to wake this system from S3. This is
>> infuriating, as I've previously installed Windows XP on the same
>> hardware, and _could_ wake it with the remote. I have yet to get to the
>> bottom of this problem - I assume the 'fix' will be in the ACPI related
>> portions of the kernel. Anyway, the point is I have to suffer the
>> indignity of pressing the power button on the case to wake the box
> manually.
> 
> Thanks for the help!  Unfortunatly, due to equipment location, this is a
> show stopper for me.  Something like this may cause me to go with a low
> power unit and a lot of RAM, and just load everything into a RAM disk and
> spin down the drive with a fanless system.
> 
> 
> Thanks again for your help,
> Ben
> 

I've recently been here myself. You need a recent kernel, 
something similar to a Microsoft/Philips eHome USB receiver 
and some luck on the motherboard front.

You need a motherboard which supports +5v standby supplying 
  at least one of the ports.

I have an Asus A7N8x-x, which has the required hardware. A 
jumper on the motherboard enables +5vSB to a selection of 
the ports - possibly just one.

2.6.16+ (I think) kernels have:
Device Drivers  --->
USB support  --->
[*]   USB selective suspend/resume and wakeup (EXPERIMENTAL)

I also have most of the ACPI stuff turned on.

Reboot into the kernel with this option and you'll have 
/proc/acpi/wakeup. By default, nothing is enabled.

I have:
echo USB1 >/proc/acpi/wakeup

in my local startup script. This enables wake from the USB 
port in software.

You need to get the correct physical port and wakeup device, 
  however. If you enable the wrong one (one that isn't 
powered from 5vSB), the motherboard will not shut down.

Now, suspending should be resumable from S3. Not sure about 
S4, though.

Anyone contemplating power saving on their boxes should 
beware of "standby" however. My machine (above motherboard, 
GeForce 6 series GPU) consumes 115w (measured with a sorta 
proper meter) at idle. This INCREASES to 120w in standby. 
Thanks, Asus or Nvidia or whatever gods are being bloody minded.

Cheers,

Allan.