Please Help Me With My PC

[Biggsy]

I've already done it.  I wasn't going to admit that if you told me it was dangerous. 

But what if another device in the house leaked some current to earth at the same time as I was plugged in?  Couldn't it come up to another socket, so to speak?

[Feanor]

Not so long as your earth is conected back to main earth point near the CU.

What *can* happen is that if the 'earth' conductor ( CPC ) on a ring-main becomes disconnected in 2 places, leaving a section of the ring-main with a floating 'non-earth', then yes leakage caused by mains filters etc on the same non-eathed segment can cause the 'non-earth' to float at half mains voltage.

You'd feel that as a slight tingle.
But the source impedance of these filters is should be high, and that will limit the current available to tingle you.
However, in the case of a fault, it's possible the non-earth could become proper live.

Make sure your earth is a proper earth!

[Biggsy]

Ta.  How do I make sure my earth is a proper earth without lifting the floorboards, etc?

My computer is not in the same room as the CU.

[clarion]

Whoa! What?  Antistatic precautions?  Does this mean I shouldn't wear lycra while furtling about in a computator?

[Tim Hall]

aye. And don't stroke the cat with the memory module either.

[hulver]

Leave the computer plugged in, put switch the wall socket off.

Touch the metal case before you touch the memory sticks.

Should be fine.

[Biggsy]

Also don't vacuum clean the innards of your computer with a brush extension that will charge itself with static as you sweep.  Yes I have been there and killed a motherboard doing that.

Leaving the computer plugged in could be dangerous if the case is connected to earth and your earth is not a proper earth.

[Feanor]

I'd not go so far as saying it's dangerous, quite far from it really.
There would need to be multiple faults present to have a 'live' earth.

-The Ring Main CPC ( 'earth wire' ) broken at 2 places;
-A device with a serious earth-fault plugged into the floating section;
-No RCD protection.

TBH, it's a vanishingly fairly small risk, which I personally don't worry about.

If you want to check your earth continuity, then one way is simply with a multi-meter and a loooong wire.
Buzz it out from the main earth point beside your meter to each socket in turn.

I'd also reccommend equipotential bonding on any tinfoil hats, too 

[border-rider]

Leaving the computer plugged in could be dangerous if the case is connected to earth and your earth is not a proper earth.

Not having a functional earth is potentially dangerous in a lot more instances that just when changing memory.

[Biggsy]

TBH, it's a vanishingly fairly small risk, which I personally don't worry about.

Neither will I then.  Thanks again.  I don't even wear a magic hat for cycling, let alone when fixing buggering up electrical things.

[Polar Bear]

PB, I've got some RAM ripped from a laptop in my desk drawer. DDR2 5300, not sure of the size, cos the print's too small and I left my glasses at home.

Normally I'd bite your hand off but the charity only uses desktop machines - less attractive and thus less likely to walk off.   Thanks very much indeed for the thought though Tim.

[nicknack]

Well, I followed the advice above and got a couple of memory modules to upgrade this old XP machine to 3Gb. After 3 false starts (2x"a network cable is unplugged", 1xcompletely seizing up) it seems to be ok. I think it was just doing the old XP thing of, "How dare you fiddle with the hardware? I'm just going to be awkward for a bit to teach you a lesson". Anyway, it seems to running somewhat quicker than it did - it even booted up more quickly.

[clarion]

Well, I have my memory.  Need to fit it at some point.  Tomorrow will do if it's too snowy to play out

[tonycollinet]

Fitting is easy - cover off. Earth self as described above (pc plugged in, but socket switched off - touch pc metal work - repeat frequently)

Pull memory slot locking tabs outwards on old memory and remove. Push new memory (reasonably firmly) into place (it can only fit one way round - line up notch on memory module with locating tab in slot. When they are pushed into place, the locking tabs will click towards the module, but not fully engage. Push the locking tabs in (to engage with memory module on each side). You may want to try first boot up with the cover still off - to ensure everything is seated correctly. Perfectly safe, all high voltages are safely contained inside the Power Supply. Just avoid dropping anything metal (eg case screws) into the case while the cover is off so as not to damage anything.

Cover back on - Job done.

If you have 4 memory slots (which I doubt) you'll need to make sure you are using the correct two - you may need to download the motherboard manual for this. Your crucial scan says you only have two, so no problem

[clarion]

Indeed.  Job done.  That was an awful lot easier than I expected.  I don't know if it's made a big difference or not, but it didn't cost much, and it was simple with you guys holding my hand

Now to sort out the DVDVD player.

[Polar Bear]

Turn it on, find out.   The machine should actually respond now...   

[clarion]

Cheeky beggar.  And there was me just packaging up the old memory for you...

[clarion]

Right.  I knew it had been going too well so far. 

I've deleted a couple of the media players, leaving Windows media player, which ain't good, but I suspected that the others might have been causing an issue.  Oh - and Realplayer, which I think I still need for BBC radio.

But now I don't seem to have any audio output.  Windows says I don't have a decoder or something.

Any clues?

[Feanor]

Well, what *exactly* were you trying to do when the error occoured?
And what was the *exact* words of the error message?

In the meantime, check if all the hardware is in order in Device Manager.

What version of windows?
If Win7, then Win-key+Pause/Break will give you a system overview.
There will be a 'Device Manager' link in the LHS.
Otherwise, goto Control Panel -> Device Manager.

Look through the list of devices.
Look at 'Sound, video, and game controllers'.
Is anything banged out with an error / warning?

If all is well in Device Manager, then go into Control Panel -> sounds, and check it's using the devices you expect.
Sometimes, there may be more than 1 sound device ( eg some on-board MOBO thing, and also an add-in card ).

[clarion]

Thanks.  I realise that was a bit vague.  I'll try the disc again and see what the error message is.

I have XP.  No Device Manager in Control Panel, though.  Might it be in one of the other options?

EDIT: d'Oh!  There's a Sounds and Audio Devices option.  For some reason, it doesn't think that there's a speaker attached. 

[Feanor]

Disk? so you're trying to play a DVD?

OK, googling:

To open Device Manager, click Start, and then click Control Panel. Click Performance and Maintenance, and then click System. On the Hardware tab, click Device Manager.

<Starts up a VM:>

Or go Win-key+Pause/break
<pop-up appears>
Hardware tab.
Device Manager.

[Feanor]

EDIT: d'Oh!  There's a Sounds and Audio Devices option.  For some reason, it doesn't think that there's a speaker attached. 

OK, then you need to go to Device Manager and see what it says.

[Biggsy]

Is there not even any system sounds?  No bing bong when you plug in a USB device, for example?

The computer doesn't normally know of care if a speaker is attached.  I suspect you just need to ensure the audio driver and its settings are ok.

[clarion]

I'm playing a DVD as it's the only audio source I've got, though I've tried Youtube as well.  Actually, now I think about it, I probably have TGL's iTunes on here too.

Error message:

Windows Media Player cannot play the DVD because a compatible DVD decoder is not installed on your computer.

I don't have Performance & Maintenance on Control Panel.  I'll have to leave it for tonight.

Thanks for your help

[Biggsy]

Try Feanor's alternative suggestion!:

Win-key+Pause/break
<pop-up appears>
Hardware tab.
Device Manager.

Have a play with the audio settings there.  Failing everything else, uninstall and reinstall the audio driver.  And ensure your speakers actually are plugged in!    (properly)