Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

rigormortis

macrumors 68000
Original poster
Jun 11, 2009
1,813
229
this is news to me. apologies if this is well known. this is my third mac mini
and i didn't own the 2012 model

if your Haswell Mac mini (late 2014) is sleeping, with its power light flashing

the power plug can be disconnected and the light continues to flash. and when power is restored, the mac will wake up at a keypress or a mouse movement. with no indication anything was wrong. it doesn’t even seem to restore from a hibernation, i feel if that was the case the restore would of taken longer, given its 5400 rpm drive and no ssd


if the power plug is disconnected with the unit fully on then it drops power

i think this computer is so low power that the capacitors or watch battery is enough power to keep the computer’s ram contents alive

what could be supplying power ?? the external hard drive I'm using?? the hdmi cable??? this is weird!

update
the first time i noticed this , it was when my ups failed and the mac was still alive
the second time i did this, it worked
the third time i did this, it dropped power like it would do nomally

so it seems to me that the residual charge of the mac minis capacitors is keeping the ram content alive
for however long the time limit is.. 30 seconds?? weird
 
Last edited:
Wow - this is amazing... the kind of amazing advancements that truly define an Apple product.

A lot of people on these message boards are obsessed with bullet point advertisements that don't mean a lot in day-to-day usage.

I care more about buying the latest high quality innovations from Apple, because I trust that they know how to design the best products. Even things like this which would be advertised to no end by a competitor are no big deal to a company like Apple and they forget to even mention them. LOL! Amazing...

Good find btw.
 
Wow - this is amazing... the kind of amazing advancements that truly define an Apple product.

A lot of people on these message boards are obsessed with bullet point advertisements that don't mean a lot in day-to-day usage.

I care more about buying the latest high quality innovations from Apple, because I trust that they know how to design the best products. Even things like this which would be advertised to no end by a competitor are no big deal to a company like Apple and they forget to even mention them. LOL! Amazing...

Good find btw.
WOW, did you ever heard of capacitors? Try to connect some USB device and this so called feature will vanish, magically as device draw will kill the caps in a few seconds. Pretty sure 2012 would do the same when no peripherals are connected (for example when using BT KB and mice).
 
I believe all Macs have had this for years though it may act differently when the power is lost.

I have a 2008 black MacBook that I've been using without a battery for a few years now. If I accidentally pull the magsafe from it's side, the MacBook goes dark. Once I connect the power and press the power button, after a few seconds, it goes right back to the app I was using as if I never unplugged it.

My 2012 Mini is the same way.
 
I've seen capacitors only keep power for a split second. A lot of times I'll tell people to cold boot their computers by shutting down Unplugging and pushing the power button to drain the caps. When my ups dropped its power my Mac mini was without power for probably 30 seconds and it was fine because it was asleep. That part I never noticed before. I had to keep trying to make sure it was the caps. It would of been really impressive if it was the watch cell keeping the ram. But sadly no.
 
I've seen capacitors only keep power for a split second. A lot of times I'll tell people to cold boot their computers by shutting down Unplugging and pushing the power button to drain the caps. When my ups dropped its power my Mac mini was without power for probably 30 seconds and it was fine because it was asleep. That part I never noticed before. I had to keep trying to make sure it was the caps. It would of been really impressive if it was the watch cell keeping the ram. But sadly no.

Usually, when troubleshooting electronics support reps would ask to keep unit without power for more than 30 secs to fully reset (allow caps to discharge). BTW, it is good that it does not drop right away, but you still better off to use backup ups. I usually, do not connect UPS to the computer. Otherwise, when power goes off - it will wake up computer and it will keep it running until it kills the battery. If computer sleeping it could last for hours instead of 10-20 mins. Hopefully, as usual, power is restored within hour or less.
 
this is news to me. apologies if this is well known. this is my third mac mini
and i didn't own the 2012 model

if your Haswell Mac mini (late 2014) is sleeping, with its power light flashing

the power plug can be disconnected and the light continues to flash. and when power is restored, the mac will wake up at a keypress or a mouse movement. with no indication anything was wrong. it doesn’t even seem to restore from a hibernation, i feel if that was the case the restore would of taken longer, given its 5400 rpm drive and no ssd


if the power plug is disconnected with the unit fully on then it drops power

i think this computer is so low power that the capacitors or watch battery is enough power to keep the computer’s ram contents alive

what could be supplying power ?? the external hard drive I'm using?? the hdmi cable??? this is weird!

update
the first time i noticed this , it was when my ups failed and the mac was still alive
the second time i did this, it worked
the third time i did this, it dropped power like it would do nomally

so it seems to me that the residual charge of the mac minis capacitors is keeping the ram content alive
for however long the time limit is.. 30 seconds?? weird


That is the advantages of the LPDDR3 memory they is being used has a max power requirement of less than 200mW and allows for "deep power down" and Partial array self-refresh. Which means you can have you computer go in to sleep mode without having to have to memory refresh.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.