PSU Kettle lead/PSU questions

[nsymons]

This system:

Asus P5KC
4GB Crucial Ballistix DDR2 800
nVidia 8800 GTS 320Mb
Intel Core 2 Duo E8400 3GHz
Intel 80Gb X25M SSD
2x Hitachi 160gb old HDDs
Vista x32 recently replaced with Win 7 x64
Seasonic SS 650HT (650w PSU)

Both vista 32 and win 7 64 had problems with hanging on startup. Particularly bad starting from cold (rather than reset.) It would hang during initial MS screen e.g. green loading bar in vista or 4 multicolour light thing in win 7.

I was using ms config to selective startup to try to identify the problem but got rid of all non-windows programs and processes without helping. While doing this the system suddenly failed to POST.

It is still in this situation despite change of Mobo. I have tried the GFX card in another computer and it seems to be working fine. On power on the fans all spin up, hdd LED flashes once but there is no output to the screen and no POST. There are no mobo failed POST bleep signals either.

Should the system still POST if the processor is fried or is this more likely to be a PSU problem? Does anyone have any idea what is going on? Cheers.

Written from my laptop!

[vudluxi]

Could be MB but from personnel experience sounds more like a faulty memory stick

[nsymons]

I have 4 x 1Gb Crucial balistix DDR2 800

I have tried booting with just one stick of RAM and swapped them around so I don't think that's it TBH.

[nsymons]

Does anyone know?

Will a mobo begin to POST if the CPU is dead or will I just get a black screen as described?

[Malketh]

Granted it's been a while since I've had a dead CPU, but if I remember correctly a mobo will *not* POST if the CPU is bad/dead just as if it wasn't in the socket at all. If you got another one around that'll fit the socket that you know works, swap it in just to see if it posts.

[nsymons]

Yeah, that's the problem

No other CPU and no other PSU to use to check it out

Will probably try Tottenham Ct Road computer fair tomorrow.

I think there may be some guys there who could test this out for me and possibilities to but kit to replace dead parts.

[nsymons]

Woo hoo.

Found the problem, Blown fuse in kettle lead to PSU. Found it more or less by accident "it can't be the lead but I've tried everything else so what the hell..."


I was using a 10A rated lead with a 5A fuse (as supplied) but I suspect it came from a printer or something waaaaay back when. It doesn't seem to b up to powering my whole system.

Question: what rated kettle lead (in terms of ampage) do I need to run the system above?

Cheers

[Jetfire]

5 amp fuse shouldn't have blown with your 650w PSU unless it is shorting.

Also, if the fuse had gone how would it have even powered on?

[nsymons]

Well I've put a new 13A fuse in and it seems to be working again.

Initially I was getting dodgy hangs on startup, especially when booting from cold instead of restart. Then the system failed to POST, fans would spin up but screen would stay blank, no POST failure bleeps. Finally it stopped providing any power alt all.

Seasonic 650W PSU says it draws up to 10A on the side of the case so I guess it could blow a 5A fuse.

Slightly concerned having a 13A fuse in a cable only rated for 10A but if the PSU only draws 10A max and 650W is a bit of overkill for my system anyway so I hope I should be OK.

[Krikkit]

A 10A max kettle plug sounds a bit weird - they're designed to comfortably cope with >20amps to avoid resistive heating etc while carrying 13A for a kettle.

[nsymons]

I have a couple like that. check out the plug that goes into the PSU. I have 2 the same that both have 10A embossed on them, as does the one in the back of my LCD TV.

[Krikkit]

Weird. You would've thought, being compatible with a kettle they would be much higher rated than that.

[Ravenheart]

Only thing that worries me here is why you're using a Kettle lead for your pc? Don't you have a normal psu power connector? Or are you actually referring to that as a Kettle lead?

[tonpal]

Originally Posted by nsymons

Well I've put a new 13A fuse in and it seems to be working again.

Initially I was getting dodgy hangs on startup, especially when booting from cold instead of restart. Then the system failed to POST, fans would spin up but screen would stay blank, no POST failure bleeps. Finally it stopped providing any power alt all.

Seasonic 650W PSU says it draws up to 10A on the side of the case so I guess it could blow a 5A fuse.

Slightly concerned having a 13A fuse in a cable only rated for 10A but if the PSU only draws 10A max and 650W is a bit of overkill for my system anyway so I hope I should be OK.

Power = Voltage x Current

therefore

Current = Power/Voltage

Assuming you are in the UK, on the primary (230V) side of the transformer the current will be:

Current = 650/230
= 2.83 A

I would put a 5A fuse back in. It could have been a dodgy fuse.

[capnPedro]

Originally Posted by Ravenheart

Only thing that worries me here is why you're using a Kettle lead for your pc? Don't you have a normal psu power connector? Or are you actually referring to that as a Kettle lead?

The normal PSU cable is a kettle lead.

There are also cloverleaf and figure-8 connectors for laptop power bricks.

[IanW]

Everyone calls it a kettle lead because most first saw one plugged into their kettle.

The connector is offically an "IEC 60320 type C13"
The true kettle plug is a type C15 which has a higher temperature rating (120C vs 70C).

[g3n3tiX]

I've got this one on my Dark Power Pro 750. Rated at 16 A. Much bigger than a standard C15.

[Pookeyhead]

If you now have a 13A fuse in it, be careful, because that's much higher rated than you need, and it may not blow should a problem require it to do so.

Every PSU lead I've seen has had a 5A fuse in it.

[Cupboard]

Originally Posted by capnPedro

The normal PSU cable is a kettle lead.

Actually I don't think so. "Normal" PSU leads are cold IECs rated to 6A or 10A usually, depending on the cable diameter. Kettle leads have a little notch out of them and are rated to 13A I believe

[IanW]

Smooth = 6A (C13)
Notch = 10A (C15)