OTish - computer soak testing ...

[Jethro_uk]

Our lad managed to spunk quite a bit on a s/h MacBook (I think he has ambitions about making music, and video editing).

With tiresome predictability, it started having some "issues", so I got roped in. Apparently "it kept restarting" ....

A crash course in MacOS later, and I managed to get it to boot by zapping the NVRAM. Once in, there was an OS update to install. I tried doing this, but the damn thing started beeping ...

3 beeps every 5s indicates a memory issue (machine was still running though).

I opened it, and swapped the memory sticks, rebooted, and reinstalled the update. Booted fine. Rebooted, booted fine.

After that, I decided to make sure it could reboot 10 times in a row ... of course it failed after 8 :(

A hard reset later, and repeating the reboot cycle, and I'm now on 17 flawless reboots (I'm ssh'ing in and issuing "sudo reboot 0")

make that 18

at what point should I call it a day and declare it fixed (until the next time :) ) ?

[Chris Bartram]

Personally, I'd download an intensive memory test and run it overnight. Memtest86 or similar, assumimg it supports Macs.

[Jethro_uk]

It would have been my first action for a x86 machine ...

Anyway, 22 and counting :)

[Bob Eager]

Overheating? Son's laptop did that and the fan was clogged with crud.

[www.GymRatZ.co.uk]

Might be fine while it's warm and go wonky when it cools down.

[Jethro_uk]

Good point - although I couldn't see too much when I swapped the memory sticks.

[Brian Gaff]

Well ram is notoriously difficult to sort. I'd hope its easy to get at and maybe you can find out which stick it is, or maybe its more to do with connections?

After all if you have not actually changed anything, potentially, nothing has changed at all if its inside a chip, the heat can fix it until it cools down again and the fault returns. Another thing to consider of course is the psu components themselves, just like in tv boxes the capacitors dry out and tend to let crap get to the software. Brian

[Brian Gaff]

Its mostly the filters, similar to those on cleaners that have the problem these days I notice. However I have an old desktop which has started to do shut downs despite having the heat sink gell renewed etc, I suspect that the actual age of the processor is just making its internal thermal conductivity lower than when it was new. One can help it by running the fans flat out and you can see the core temp come down, but it goes up fast if the fans are reduced despite a lot of cleaning etc. I have to assume its just age. Brian

[RJH]

That'd be my guess. Maybe try one of the fan utilities - I use iStat (ISTR a free trial) - and have a look at the temperatures, CPU use and fan speed.

[Jethro_uk]

Tx for all the tips.

FWIW, there's something iffy about this machine, as the onboard diagnostics are missing, suggesting a HDD reinstall/replacement.

I've managed to get the internet recovery working and am reinstalling the OS - which a *lot* of sites seem to recommend ?????? I'm doing this in the hope it will reinstall the diagnostics, since the MacOS Memtest86 utility won't work on this version of hardware.

Quite impressed that it managed to get the WiFi credentials off the HDD during boot, and then carry on ....

[Tim Watts]

Get a copy of memtest86 on a bootable USB stick and run that overnight.

That's one of my standard soak tests :)

[Tim+]

A bit OT perhaps, but my wife's 7 year old macbook pro has been given a new lease of life with a SSD upgrade which has rendered it much more useable

Definitely worth doing.

Tim

[Jethro_uk]

If the memtest is OK, I'll mention it to sprog ...

[Jethro_uk]

Running as I type :)

[Jethro_uk]

Why not ? Having failed at 22 reboots, there's clearly something wrong ... the "missing" diagnostics partition suggests the OS has been (badly ?) reinstalled.

CeX. Personally I wouldn't touch them with a bargepole, but kids ...

I'd be curious about the issues of selling secondhand machines like this without the all-important (i.e. Apple charge for them) installation disks. Seems they have to be ordered - aren't available online.

[Jethro_uk]

Well I've managed to boot it from a USB and am running memtest as I type.

That's my (mild) worry.

Everything ages ... it's the nature of things.

[RJH]

Depending on the age of the machine, I don't think they're needed any more.

If iStat isn't showing anything untoward, ask on uk.comp.sys.mac - plenty of knowledgeable folk on there.

[Dave Liquorice]

Yep, my 2009 vintage PC started to become unreliable booting and eventually refused to play at all not even any POST beeps. Examined motherboard, all but one of nine 680 uF 4 V electrolytics had over pressured and pushed the rubber bung out of the case. Bit of a faff getting them out, bunged in nine new 680 uF 10 Vs, trimmed CPU heatsink as the new ones are three mm higher an fouled it, power up, beep...

2009 is in theory a couple of years past the "capacitor plauge" but as all the other electrolytics on the board are fine and effectively only that value and wierd voltage had failed, I recokon they were just slow clearing the supply chain. £4.78 delivered for 10 x 680 uF 10 V.

[whisky-dave]

Did you replace them with identcal caps, usually it's best to try to got for the 105C if 85C were fitted you can get 130C too but the size can be physically bigger.

[Andrew Gabriel]

Extremely common problem at Repair Cafes (at least, those that handle laptops).