If a button has to be hit it would be too late. The switching should occur when the PC detects that power is being lost. (And it mightn't be possible to make the switch before the power is lost for an instant.)

Basically this idea of a 'HIBERNATE BUTTON' is aimed at thehome pc users who cannot afford a UPS which could last for a few hours.It is only an option - it could be activated before switching on a PC.

If they cannot afford a UPS, they cannot afford the premium your proposal would add to the price of a computer.

Mind you, more and more notebooks are being sold, and those have built in batteries anyways.

We are not talking about laptops here, this concept is meant for thedesktops. A normal UPS for a Desktop costs about 50-100 USD andgives you a back up of about 10-20 minutes. We are looking at thehibernate button to keep the unsaved information (Without using the PC) for about 24-30 hours.

You aren't talking of a button. A button has nothing to do with things. If power goes out, everythine (to the last save) is lost. No button pushing will bring it back. A battery is what you want, as that is what will keep the memory running. And adding a battery and its control circuitry will add a premium cost to a computer. The longer the desired backup the larger the battery that will be needed, and that will also increase the cost.

I am not saying it isn't possible from a technical standpoint, it is just not practical in todays home/office PC market, where cost margins are as slim as they are, and people are looking for the bottom dollar to spend. If they want a UPS, they will purchase one separately.

Costs of most electronic components/MIAH lithium batteries arecomming down drastically. Things we could not imagine are beingafordable today. You still not have understood my point, a UPS willlast for a few hours, we are looking for a cheap back-up tolast atleast a day.

For a days storage, there will be a notable cost of storage batteries, not to mention the development costs. You don't need to keep it for a day anyways, just long enough to save to the HDD or a flash drive.

Still, the computer buying public won't want to pay a premium for that, which it will end up being most likely.

basically all you need is a standard ups and you have plenty of time to either save your files or put the computer into a regular hibernate mode, which uses so little power that the ups might actully last a day, the other possibility is to just change the function of the power button circuit to hibernate, easily doable on a pc, and link that circuit to the ups, so as soon as it switches to battery, it automatically goes into hybernate. the problem with any of these systems is that if your power is out longer than expected, say a few days if a transformer station goes down, the battery dies anyway and the work is still lost, the real solution is to just keep the computer on long enough to save your work and shut down.