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Quadra 840av and booting
Posted by: toples50 on 2019-02-18 07:52:21
I had my 840av for a year in the basement.Today I tried to boot it up.Power up but no chime so,no picture.After 10 tries finally i heard the chime and have normal picture.Then again nothing.The same.I don't have a battery.Have to recap the motherboard?
Posted by: LaPorta on 2019-02-18 07:58:00
Probably both, to be honest. Definitely needs a recap no matter what.
Posted by: toples50 on 2019-02-18 08:56:56
I will post pics from the motherboard tomorrow. 
Posted by: AwkwardPotato on 2019-02-18 08:58:58
Have to recap the motherboard?
Definitely recap it while it still shows some signs of life. The Q840av is notoriously difficult to revive once the damage is too far gone.
Posted by: toples50 on 2019-02-18 23:26:46
Pictures from motherboard.

IMG_0143.jpg

IMG_0144.jpg

IMG_0145.jpg
Posted by: Byrd on 2019-02-19 02:43:12
Original caps = time to recap.  They look alright, but likely to be marginal and in need of replacement for your startup issues.  The 840AV is one of those Macs that is prone to fail, and fail hard without much chance of resurrection if you leave it for too long.

My 840AV had similar startup issues and it wasn't until a full recap, and extensive deep clean of the board does it work well.   I replaced caps on the board ~ 5 years ago but didn't clean the cap residue particularly well, last year I rebuilt it again and it's thankfully OK 😛

Posted by: LaPorta on 2019-02-19 02:46:29
My Mac Portable had weird symptoms with rolling lines in it's LCD until I re-soldered and cleaned up some chip feet that had become tarnished with cap good. You never know what you will fix by refreshing things.
Posted by: AwkwardPotato on 2019-02-19 08:27:45
One of the leads on the AT&T DSP already looks like it's being eaten by the cap goo, although that's probably not the cause of your boot issue. Even if you aren't able to recap the board immediately, it would be a good idea to wash it as soon as possible to prevent more damage.
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