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Jim Ford
22nd October 2016, 02:09 PM
I've a W10 machine that I only use for PS.

It was working fine a couple of day ago, but now won't boot.

The symptoms are:

On power up the screen displays "Reboot and select preferred boot device or select boot device and press a key". Before this is shown, the screen briefly flickers, sometimes showing the BIOS splash screen for a brief moment (1/10 second or so - just enough to recognise). No lights show on keyboard and no beeping.

Power cycling (or pressing reset) with any function key or makes no difference.

Disconnecting the keyboard doesn't result in a 'no keyboard' message.

Trying different boot media makes no difference (I can't get into the bios to alter the boot media anyway)

I've taken the cover off and 'wiggled' all connections.

I'm beginning to think it's the MB or CPU that's at fault. The boot sequence is not getting as far as the BIOS detecting the KB or other hardware and reporting.

Ideas, anyone?

Jim

Ian
22nd October 2016, 02:15 PM
Maybe the battery on the motherboard (often a button cell)? Can you get into the BIOS and see if the time and date are correct. From there you should also be able to see if the attached hard drives are being seen.

Ian

Jim Ford
22nd October 2016, 02:30 PM
Can you get into the BIOS and see if the time and date are correct. From there you should also be able to see if the attached hard drives are being seen.

No, I can't get into the BIOS (no BIOS screen is displayed). Also, the keyboard lights don't flash and no keyboard error is reported if I disconnect it. CPU and PS fans run.

Jim

pault
22nd October 2016, 03:15 PM
Have you tried booting into safe mode?

Jim Ford
22nd October 2016, 05:00 PM
Have you tried booting into safe mode?

It won't boot in any mode - full stop! The BIOS screen doesn't even show (except as a brief flicker as I initially mentioned), so I reckon the BIOS isn't getting loaded into RAM from the firmware and initialising the system.

I'm still thinking MB or CPU.

Jim

shenstone
22nd October 2016, 05:09 PM
I'm beginning to think it's the MB or CPU that's at fault. The boot sequence is not getting as far as the BIOS detecting the KB or other hardware and reporting.

With the symptoms you describe that is quite possible - if you can't get to the BIOS then its not passing the POST (power on self test for this who don't know)

The only thing I can think of that is some non bootable device (such as CD) was left in the primary boot device - if so remove it (unplug CD drive inside if needed)

or give the system some bootable media (e.g. Windows setup disk) you may need to create this on another PC if you do not have such already

EDIT - I guess a cable fault to your disk drive is also possible I've seen that before where a fan was touching a cable and wore through it - normally there are spare connectors on IDE cables or replace a SATA cable

regards
Andy

Jim Ford
22nd October 2016, 05:21 PM
With the symptoms you describe that is quite possible - if you can't get to the BIOS then its not passing the POST (power on self test for this who don't know)

or give the system some bootable media (e.g. Windows setup disk) you may need to create this on another PC if you do not have such already

It's not getting past POST and therefore won't boot off anything - W7 installation media or bootable USB stick (Knoppix).

The only thing that puzzles me is what part of the system is giving the "Reboot and select preferred boot device .. etc" message, if the BIOS isn't firing up?

Jim

birdboy
22nd October 2016, 05:26 PM
The only thing I can think of is that it is going through one of these Windows updates and just needs to be left to get on with things. How long have you left it powered up?
Does it have an internet connection?

shenstone
22nd October 2016, 05:30 PM
Then Lower level hardware issue looks likely. I would

Check cables
Check all hardware items are seated properly (memory, cards etc.)

Regards
Andy

Jim Ford
22nd October 2016, 05:58 PM
Then Lower level hardware issue looks likely. I would

Check cables
Check all hardware items are seated properly (memory, cards etc.)


I've checked cables, plugs, CPU and RAM seating to no avail, so I reckon it's a hardware problem.

As I mentioned before POST doesn't even appear to run as there's no keyboard lights flashing (they're all 'dead'), no beeping and no error reporting, other then the initial "Reboot and select preferred boot device etc." message.

Jim

Jim Ford
22nd October 2016, 06:00 PM
The only thing I can think of is that it is going through one of these Windows updates and just needs to be left to get on with things. How long have you left it powered up?
Does it have an internet connection?

The machine needs to boot to be able to update!

Jim

Ricoh
22nd October 2016, 06:44 PM
Long shot - have you tried a live Linux Distro in the DVD drive?

Jim Ford
22nd October 2016, 07:52 PM
Long shot - have you tried a live Linux Distro in the DVD drive?

It won't boot on any media, because it doesn't detect any, bootable or otherwise. The machine doesn't even get through the POST! I'm convinced it's a hardware problem.

Jim

Ricoh
22nd October 2016, 08:16 PM
Back to Ian's post #2, did you check the battery / replace it as suggested.

Naughty Nigel
22nd October 2016, 08:16 PM
I'm beginning to think it's the MB or CPU that's at fault. The boot sequence is not getting as far as the BIOS detecting the KB or other hardware and reporting.

Ideas, anyone?

Jim

At a guess I would say it is a motherboard or memory fault.

There might be a button somewhere on the motherboard to do a general reset of the BIOS and suchlike. (Our HP desktops have them.) That might at least get you into the BIOS setup (usually F2 or F10 when booting up).

If it were the CPU I wouldn't expect it to do anything at all, or perhaps start booting but then blue screen or reboot.

It may also be a fault in attached hardware which is preventing the motherboard from executing the boot up sequence. I have known faulty memory modules and hard drives to cause similar problems.
On one occasion I burnt my finger on one of the memory chips as I removed the module!

If you have more than one memory module I would try removing one at a time to see if it makes any difference, (making sure there is always one in 'Slot 0'.

I would also try disconnecting the hard drive and DVD. If it is one of these it should ask for a bootable drive after the POST stage.

Wally
22nd October 2016, 08:17 PM
The problem(s) you are experiencing can be down to many things. Some of them not so obvious.

As you're able to post it might be of interest to try this link --> http://www.computerhope.com/issues/ch000607.htm which hopefully will give you some insight where to look and what to try out?

blu-by-u
24th October 2016, 01:18 AM
Mainboard and Power supply fault can give the same problem. Ram and graphic error, there will be beeps.

Have a close look at the capacitors on the mainboard. If any of them have exploded, that's your fault. If you are brave enough, open up the power supply. Same, inspect the capacitors.

In the past, (days of Dos) There was a virus that just wiped the BIOS rendering the whole board useless. There was no way to reflash the BIOS.

BTW, is this a PC or Mac? If PC, is it a DELL? Some of the branded PCs (DELL, Lenovo) do not use regular PSU. Please do not plug in one as it may blow up the board or PSU.

Jim Ford
24th October 2016, 10:33 AM
I removed and re-seated the CPU - no change. I then removed and re-seated the RAM and it works OK - so it was down to the RAM connection (or it could be due a problem connection on the MB and the re-seating force flexed the board enough to 'cure' it!)

I'm surprised that the POST didn't report it and IIRC older BIOS's would have. I'm wondering if the BIOS is copied to RAM before it runs, in which case I would expect it not to report non-working RAM (as I had) - but I can't see the point of doing this.

Thanks for all the suggestions>

Jim

OM USer
24th October 2016, 11:38 AM
Well done on fixing it. Its amazing what a little tinkering will do in these cases.

Ricoh
24th October 2016, 11:48 AM
If a dry joint it may be short lived. Using an ESD wrist strap (1M ohm to earth if you make your own) I'd try to further diagnose, or use a heat gun, and a can of freezer to isolate the fault. Failing that, save regularly.

Wally
24th October 2016, 11:59 AM
;tupA good result. Well done Sherlock.
Just out of curiousity, did you use a soft eraser to clean the RAM pins?

Jim Ford
24th October 2016, 12:18 PM
Just out of curiousity, did you use a soft eraser to clean the RAM pins?

No - I just inspected them and firmly replaced the DIMM.

Jim

Ross the fiddler
24th October 2016, 01:42 PM
;tupA good result. Well done Sherlock.
Just out of curiousity, did you use a soft eraser to clean the RAM pins?

That's my recommendation too. It's something that we used do in field service of early computers & photocopiers etc.

No - I just inspected them and firmly replaced the DIMM.

Jim

That may be enough to keep it happy for another long time, but I do like to make sure the connections are clean if possible.

Jim Ford
24th October 2016, 03:22 PM
I avoid abrading gold contacts with anything. The gold is very thin and besides doesn't tarnish or degrade in any way.

Jim

timboo
24th October 2016, 04:43 PM
might be worth downloading memtest onto a bootable pen drive then boot using same testing one ram stick at a time, just in case there are issues it can pickup although could be as simple as dislodged slightly as u previously stated.

Ross the fiddler
24th October 2016, 09:53 PM
I avoid abrading gold contacts with anything. The gold is very thin and besides doesn't tarnish or degrade in any way.

Jim

Yes, the gold is thin & it isn't meant to tarnish & yet some gold plated contacts can get a dark coating that looks all the world like tarnish & that is what can be suspected to be less conductive & why I & others clean it off. The soft eraser is very gentle on such surfaces & why we use it, although I usually follow it with alcohol in case it also leaves a residue (which I then buff dry). Anyhow, in your circumstance a reseat of those chips may have been all that is necessary to get a good connection again.

*chr

Daveart
25th October 2016, 09:44 AM
Hi Jim a suggestion I would make, is turn on and simultaneously press the f8 key, this should invoke the bios menu then you should be able to view the settings for test bois etc.. if you get there you should be able to reset to default.
That flicker is a bios failure to test, this process should get past this fail, before it shuts down as a protection to the motherboard.
Oh after you select default press f10 this does a resale and re try boot, then if there is a problem IE battery flat it will bleep I think twice then halt, if this happens you need to change the battery be careful though as some manufacturers solider them in.

Good luck

Jim Ford
25th October 2016, 10:09 AM
Hi Jim a suggestion I would make, is turn on and simultaneously press the f8 key, this should invoke the bios menu

It didn't because the keyboard was dead. Nothing worked whatsoever because nothing was initialised. I think it was because the BIOS needed to be copied into RAM, but the RAM wasn't working.

It's working now - see earlier post.

Jim