Intel MacBooks don't technically have a BIOS, but to reset the System Management Controller (SMC), is a similar procedure. Holding down the power button for 5sec, with no main battery, or charger present.
I found a cool tool/app called Kill CMOS which clears all the volatile CMOS info. Some laptops have a soldered on CMOS battery, making clearing difficult if no jumper is listed. I have had some odd behavior in the past, from BIOS's. After having a laptop apart for over a week, )waiting on parts) a mysterious BIOS password appeared after reassembly. I also had a Toshiba laptop with a reported bug. After plugging an iPod the system would freeze. A hard power off would result in no boot, requiring the CMOS to be cleared. Toshiba had an updated BIOS to fix the issue. I can't imagine working on computers without Google "in my pocket". Glad to hear the Acer is up and running well. Eric On Tue, 2011-03-15 at 21:35 -0400, Chris Knadle wrote: > On Tuesday, March 15, 2011 20:16:28 Cranky Frankie wrote: > > I think I fixed my netbook shutting down problem. This may be unique > > to the Acer Aspire One netbook, however. > > > > Researching it further I found recommendations for upgrading the bios > > to v. 3310. I had done that weeks ago, but there was a part I had > > missed. After the bios update, you have to unplug the netbook, remove > > the battery, and then hold the power on switch for at least 2 minutes > > to clear the mobo. The instructions were specific - one minute would > > not work, had to be two. Don't know if this drained the caps or > > whatever, but it seems to have worked (I'm hunting and pecking on > > battery power alone on the tiny keyboard right now). > > My understanding of the way that BIOS chips work is that there's a FLASH RAM > area that you program, and a separate battery-backed area with the same > information which gets copied into running computer RAM at power-up. When > you > re-flash the BIOS, you're copying over the "master" copy in the FLASH RAM > memory of the BIOS chip, but this does NOT automatically get copied into the > battery-backed RAM of the BIOS chip that is actually USED when you power up > the computer. This explains why you need to go through the special procedure > to drain all power -- because that's the only way to remove the > battery-backed > RAM copy of the BIOS in order to force the "master" to be copied over into > the > battery-backed RAM portion of the BIOS again so that it's used for bootup. > The BIOS uses a CRC checksum algorithm, and if the checksum stored doesn't > match the expected CRC calculated from the algorithm, that's what triggers > the > copying procedure from "master" to the battery-backed RAM area. > > The battery-backed BIOS RAM also contains any user BIOS choices, so if you > had > changed any BIOS settings you'll likely have to go fiddle with those again. > > What isn't clear is what holding down the power button actually does. What > most motherboards in Desktop PCs do is to have a jumper to allow the user to > short the power going to the BIOS -- and I think what that actually does is > short the +3 Volts from the lithium backup battery to ground during the time > the jumper is set to "clear". I think that's likewise what's going on with > the power button for this laptop -- while you're holding it down for a couple > of minutes, the lithium BIOS backup battery is being shorted to ground. It's > likely that the BIOS chip /also/ contains it's own internal "temporary" > backup > power source (a capacitor, or possibly even an internal lithium battery), > which is why you have to hold down the power button for longer than you'd > expect. > > There are chips that actually have a lithium battery built into them > internally, such as those found in Real-Time Clock (RTC) chips -- and these > also usually come with a RAM area that is battery-backed with the internal + > external backup battery. This is why I'm not sure if you might actually be > shorting a lithium battery that's internal to a chip or not when you're > holding down the power button. > > The point being here is that you probably don't want to do this too often, > even though it is occasionally necessary. > > > Well, unlike many computer PITAes, this one seems to finally be fixed > > (and I'll make sure to keep the dust out of the vent holes too, > > thanks). > > Glad it's fixed -- that's what matters. > > -- Chris > > -- > > Chris Knadle > [email protected] > _______________________________________________ > Mid-Hudson Valley Linux Users Group http://mhvlug.org > http://mhvlug.org/cgi-bin/mailman/listinfo/mhvlug > > Upcoming Meetings (6pm - 8pm) MHVLS Auditorium > Apr 6 - Introduction to IPv6 > May 4 - Inkscape > Jun 1 - Zimbra _______________________________________________ Mid-Hudson Valley Linux Users Group http://mhvlug.org http://mhvlug.org/cgi-bin/mailman/listinfo/mhvlug Upcoming Meetings (6pm - 8pm) MHVLS Auditorium Apr 6 - Introduction to IPv6 May 4 - Inkscape Jun 1 - Zimbra
