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Justin
07-05-2011, 08:13 PM
Been looking at someone's small format PC for them. It's an Acer Aspire L100.

Press the power switch, the light flashes, dvd drive powers up and that's it, no boot up. The dvd slot still works with the button so powers getting through.

Trying to eliminate possible problems, feeling is that there's a fault on the mobo but Acer want an arm and a leg just to test it and if it's the mobo it's expensive.

Anyone any experience fixing these small format machines?

bikertec
08-05-2011, 01:14 AM
If you have a win xp or any other operating system on cd, try to see if it trys to install. XP will tell you if your harddrive is detectable. Failing that try fitting another harddrive with a OS on.

swimwivsquid
08-05-2011, 01:37 AM
Can you get it into safe mode? Its either f1 or f8 for the Acers.....

dj_doubler
08-05-2011, 01:38 AM
would not think it was HDD related as that would come up during POST - would say HDD boot failure or give you BSOD (blue screen of death) when you boot the machine does it "POST" (make a beep) etc..?

Matt Quinn
08-05-2011, 11:10 AM
Have to agree...

If it goest through POST and into the Bios you have something to work with... If not (which is how I read what you've written) well that points to something more troublesome.

Many of these machines are built with proprietary non-standard parts and difficult to service as a result. 'Bout the only thing you can really do is check for physical damage/loose connections then go through the routine of disconnecting all ancillarys - See if that takes you to POST and first BIOS screen... Power down, re connect the HD, try again - work your way through the system bit by bit.

It's worth checking any removeable IC's (processor, RAM) for security... And if easily replaced the BIOS back-up Battery. Also beware of any litte ribbon cables between sub-assemblies.

IF it bleeps at all it's worth mentioning that the sequence of bleeps CAN have a meaning! - And if it doesn't bleep at all so can that!

gstk
08-05-2011, 11:42 AM
Take a power supply from another machine and see if it starts. If not, its a process of checking each item if you can access a spare of each. If the mobo has had it the cheapest option is buy a normal case (from £15) and new mobo (from about £20) and transfer all the working parts to the new case. Easy to do. Just make sure the new mobo supports the processor and the memory - Bits from ebuyer.co.uk check memory at crucial.com/uk to see what you need (Look at what the current model uses using their upgrade option) for about £50 you will be back in business. Acer I am sure are asking a fortune for replacement.

Justin
08-05-2011, 01:22 PM
The problem is there's no boot whatseover or I'd prob be able to work it out. Power light goes on and off and I can hear a slight hum from the machine but there's no boot so no bios/options etc.

^gstk - Small format PC so seperate case etc. doesn't work here I'm afraid.

229230

gstk
08-05-2011, 01:33 PM
Why. That's why buy a case. You don't have to buy an Acer board. Worse case is you buy a DVD drive (£15).

Matt Quinn
08-05-2011, 01:38 PM
Awkward to deal with unless you have spares you can substitute...

Could be anything... BUT ... One last suggestion; carefully open the PSU and check any internal fuses. If one's blown it's LIKELY to be for a reason... BUT very occasionally they just die of their own accord.

Apart from that - it's off to the manufacturers I reckon..

Justin
08-05-2011, 01:39 PM
There are no other working parts, it's a tiny itx Foxconn board with everything built on. I can soon put another cheap PC together but wanted to have a go at getting this one working first.

Justin
08-05-2011, 01:44 PM
Awkward to deal with unless you have spares you can substitute...

It was always going to be a shot in the dark, don't have any tiny itx boards lying around right now! lol. I try to stick to building standard sized pc's, this sort of problem doesn't happen then :-)

I'll check for internal fuses, cheers. I'm pretty sure it's something power related, the external power supply seems fine as it's getting at least some power into the unit to power the dvd drive.

Matt Quinn
08-05-2011, 01:47 PM
You should find the PSU is enclosed in its own 'shell'; which you might be able to open up. - There may be little glass fuses on the actual curcuit board. They need to be replaced with EXACTLY the same type - The rating will be engraved on the metal end-caps.

It could be the +12v line is up but something is interrupting another line...

gstk
08-05-2011, 02:35 PM
It was always going to be a shot in the dark, don't have any tiny itx boards lying around right now! lol. I try to stick to building standard sized pc's, this sort of problem doesn't happen then :-)

I'll check for internal fuses, cheers. I'm pretty sure it's something power related, the external power supply seems fine as it's getting at least some power into the unit to power the dvd drive.

Is it not a standard power supply connection to the board.

Justin
08-05-2011, 02:40 PM
No, everything's different on the mini itx board and it's an external power supply.

Justin
08-05-2011, 10:46 PM
It appears there is a small fuse on the motherboard that can cause this problem....now if only I could find it! I guess it might not look like a fuse in the traditional sense.

Matt Quinn
08-05-2011, 11:09 PM
It appears there is a small fuse on the motherboard that can cause this problem....now if only I could find it! I guess it might not look like a fuse in the traditional sense.

Obviously having not actually seen the board I can't be sure... Do a google image search for "surface mount fuse" ; they're odd little rectangular components - not like conventional cartridge fuses.

Justin
08-05-2011, 11:11 PM
Well, it#s all in bits now! I can see a few possible miniature fuses, not sure how to test them but at least it's all come apart.

Matt Quinn
08-05-2011, 11:23 PM
Biggest challenge is identifying it! - They're tested like any other fuse once out... Just a simple continuity test. Otherwise you'd need a schematic and a meter to trace the power lines.

Some actually are in little holders rather than soldered on...

Matt Quinn
08-05-2011, 11:33 PM
Doh! duplicate post! - Sorry!