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linw
10-10-2013, 11:53 AM
Anyone done one of these? Can't find a K51 disassembly on the net.

Some cmos battery replacements seem to require a complete disassembly. NOT keen on this! Maybe time for an expert lappie repairer or new machine, methinks.

(This 4 yr old laptop won't keep time and has delays in posting prior to win7 loading).

wainuitech
10-10-2013, 12:30 PM
Anyone done one of these? Can't find a K51 disassembly on the net.

Some cmos battery replacements seem to require a complete disassembly. NOT keen on this! Maybe time for an expert lappie repairer or new machine, methinks.

(This 4 yr old laptop won't keep time and has delays in posting prior to win7 loading). Haven't done one, But if you have a look at the motherboard K51AC-K51AB-k70AC-K70AB-motherboard (http://www.aliexpress.com/store/product/K51AC-K51AB-k70AC-K70AB-motherboard-for-asus-laptop-SOCKET-S1/107626_561698064.html) Top picture, bottom right hand corner shows you where the CMOS battery is, so its a start to see if any panels are in the same area :2cents:

wainuitech
10-10-2013, 12:44 PM
This video is for the k50 - May be close enough http://www.youtube.com/watch?v=yldJUORM_Co If its the same, 5 minute job :p

linw
10-10-2013, 02:02 PM
Thanks heaps, WT. The guy who owns it seems to think that the K50 in the clip matches his. He is going to have a go with the five screws and ring me back.

Hopefully he'll see the 2032 and how to replace it!!

Let you know how we go.

linw
10-10-2013, 02:16 PM
Well, it's not exactly the same but near enough. The K51AC has another small panel alongside the bty and there is another screw that enables the main back panel to come off.

But, this does expose the 2032! He is going to bring it over soon so will check that bty and replace it. And hope that is what is wrong!!

Will also get a disk checker running as well.

linw
10-10-2013, 03:49 PM
Oh, well, 2032 reads 3.27V. So, not that. Anyway, a dead cmos bty usually results in a prompt to set the BIOS up and has times/dates set to initial settings.

Took 10 min to start loading windows so fault still there. On power up it sniffs the DVD drive immediately so the POST is starting. But with a black screen and no other action it is hard to know what it does for the other 10 min!

The drive is being checked for hard errors as we speak. After that, I am lost for ideas. Sounds like a hardware problem - bad capacitor taking 10 min to charge???? Would the POST just sit and wait??

He will try to keep it going by using sleep mode rather than shutdown.

I HATE having to give up but I am also a wee bit realistic!!!!!!!!!

Thanks for help, WT. That YT clip was useful.

Speedy Gonzales
10-10-2013, 04:43 PM
Check that the hdd is the bootdisk too. If its on dvd it can take longer to boot into windows. Also if its got a logo on the post screen disable it in the BIOS

If it does boot into windows check event viewer for errors

wainuitech
10-10-2013, 05:34 PM
What you can do is disconnect /remove the HDD. Try to boot ( dont have any thing in the Optical drive either) what should happen is within a few seconds it should complain about having no boot device ( which it wont). If you suspect its the HDD, look at the activity light, if its the drive it will usually be on solid not flickering.

If it complains then its something to do with the HDD. I often find if the drive has failing sectors it will take a while to boot. Personally I use Hard Drive regenerator (http://www.dposoft.net/hdd.html) -- not for trying to fix sectors but to check drives.

That will tell you rather quickly if the drives history and the cause of the problem.

The following picture is a stuffed drive being scanned by HDD regen from the bootable CD, wont say whose it is :xmouth:

BUT did manage to do a data recovery on it afterwards and got the majority of it back.

5231

blanco
10-10-2013, 08:17 PM
Following speedy's comments, you could try a bios reset as described here:
http://www.ehow.co.uk/how_6827437_reset-bios-asus-laptop.html

Worth a try and bear in mind that a battery measured offload will read a
higher value than when under load. Substitution is always best test.

linw
11-10-2013, 09:22 AM
Thanks, guys, for the input. The BIOS had the first boot drive as the HDD. I did change that to DVD then HDD just because that is my normal setting.

When it is sitting for the pre-boot 10 min, there are no lights lit except for the power one. So, no disk activity. Like I said earlier, it just looks dead.

HDTune has been run and it didn't report any bad blocks. With chkdsk and bad blocks looking OK, it gets hard to blame the HDD.

blanco, good suggestions. If I had the machine here I would follow them as it would be worth a try.

The owner is now using sleep mode and it is starting up from sleep with no problem and the clock is staying correct. He is going to run with this and if it finally fails he will buy another.

Just one of those really puzzling ones with no satisfactory conclusion.

Once again, thanks for the help. Much appreciated.

jinja_thom
11-10-2013, 12:10 PM
This long delay in boot up is reminiscent of the old USB legacy support bios setting that used to trouble asus mother boards some years ago. I don't remember the details but I'm sure somebody must. Are there any usb devices plugged in and if so have you tried booting with them unplugged or switched off. Just a thought

linw
11-10-2013, 03:56 PM
Thanks, but no USB devices plugged in.

Mmmm, you have just tweaked my memory. I did see it BSOD once with a USB error but, at the time, I didn't link it with this delay problem. (Probably subconsciously I didn't want two problems at once!). But I did scan the error logs and there were no on-going errors reported over the last week or so when this problem started.