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Laffertytig
10-10-07, 08:05 AM
i woner if anyone here can help. ive just assembled a pc from scratch but it wont power up. surely the PSU should at least power up when i switch it on buy no nothing happens. for testing purposes i tried pluggin the old PSU into the wall as well but that doesnt even power on. i wasnt aware that the PSU had to be connected to the pc hardware to work. any ideas?

also when installing the processor it said to apply thermal grease but i dont have any, is this a problem?

i assume it wouldnt have anything to do with the LED leads as the case i have which has the LED wired differs from the motherboard manual?

windows xp
DABSVAL, 550 PSU -

creative Inspire T7900 7.1 Speakers OEM
CRUCIAL 4GB 240dimm ddr2 SDRAM
SUMSUNG 320GB 7200RPM S300 8MB harddrive
GeForce 8800GTS 320MB PCIE XT
intel Core2Duo E6750 S775 2.66ghz4mb
gigabyte S775 Intel P35 Express ATX motherboard -

there's a cdin socket on the MB Which i could swear has something in it on my old asrock MB, should there somethin in there?
also, there's an 6 pin lead which comes out of the PSU but the only place i can see where it fits is the graphics card, is this correct?

heres are the links

motherboard - http://www.dabs.com/productview.aspx...143,4294953919 (http://www.dabs.com/productview.aspx?Quicklinx=4KRT&CategorySelectedId=11143&PageMode=1&NavigationKey=11143,4294953919)

PSU - http://www.dabs.com/productview.aspx...ey=11259,50010 (http://www.dabs.com/productview.aspx?Quicklinx=39NB&CategorySelectedId=11259&PageMode=1&NavigationKey=11259,50010)

harddrive - http://www.dabs.com/productview.aspx...50429,40970000 (http://www.dabs.com/productview.aspx?Quicklinx=4LZJ&CategorySelectedId=11154&PageMode=1&NavigationKey=11154,50429,40970000)

memory - http://www.dabs.com/ProductView.aspx?Quicklinx=3R5L (http://www.dabs.com/ProductView.aspx?Quicklinx=3R5L)

processor - http://www.dabs.com/productview.aspx?Quicklinx=4MMC&CategorySelectedId=11147&PageMode=1&NavigationKey=11147

graphics card- http://www.dabs.com/ProductView.aspx...4406&InMerch=1 (http://www.dabs.com/ProductView.aspx?Quicklinx=4FFD&CategorySelectedId=11137&PageMode=1&NavigationKey=11137,48070000,4294954406&InMerch=1)

Letum
10-10-07, 08:21 AM
Have you checked you have the power leads from the MB to the power switch correct?

make sure the correct colour of wire is going to the switch, check the switch is working.

Do you have a electric "multi-meter" ?

IIRC graphics cards usualy have a 4-pin connecter to the PSU.
Don't worry about the CD-in on the MB.

danlisa
10-10-07, 08:27 AM
Thermal Paste is a must.

Do not start your PC without having applied it you will cause severe/permanent damage to the CPU.

Laffertytig
10-10-07, 08:30 AM
no i done even know what a mulit meter is.
from the PSU there is a 4 pin lead which plugs into the MB. (12v)
a 6 pin lead which i think plugs into the graphics card cos i cant see any other place where it would fit.
another lead goes to the cd drive, the FDD and the HDD. there are a few leas which are identical and dont appear to go anywhere, i assume these are for extra drives.

there's a 4 prong cdin socket but i dont seem to have anything to fit, although im sure my last rig did!

the box had the processor fan unit, and a small rectangle metal pad which i assume is the processor, or is that the pad your on about?

Prof
10-10-07, 08:49 AM
i woner if anyone here can help. ive just assembled a pc from scratch but it wont power up. surely the PSU should at least power up when i switch it on buy no nothing happens. for testing purposes i tried pluggin the old PSU into the wall as well but that doesnt even power on. i wasnt aware that the PSU had to be connected to the pc hardware to work. any ideas?I must admit that I've never tried it, but I would expect the cooling fans to come on when the PSU is connected to the mains regardless of whether or not it's connected to the motherboard. It sounds silly, but is there a voltage selector (110/230V) or an on/off switch on the rear of the PSU (near the mains lead connector) which is in the wrong place? If the old PSU won't power on either, is there something wrong with the mains socket in your house?

also when installing the processor it said to apply thermal grease but i dont have any, is this a problem?YES! Be thankful your PSU doesn't work. Don't attempt to turn on this PC unless you've got some paste in there. I'd recommend some Arctic Silver or something.

i assume it wouldnt have anything to do with the LED leads as the case i have which has the LED wired differs from the motherboard manual?Try it with just the main power switch connected...when you know it's all working you can then plug in the reset switch, PC speaker, HDD light, power light, etc...

there's a cdin socket on the MB Which i could swear has something in it on my old asrock MB, should there somethin in there?Only if you want digital audio from your CD-ROM. It's not essential. The connector will be a 4-pin small flat plug. Connect one end to the CDIN on the motherboard and connect the other end to one of your optical drives.

also, there's an 6 pin lead which comes out of the PSU but the only place i can see where it fits is the graphics card, is this correct?That's the PCI-E power cable and yes, it should be connected to your graphics card.

In addition to the 12V ATX power lead (the one you mentioned) there should also be a 20- or 24-pin power cable from the PSU to the motherboard. It's quite important!

If you're worried about your PSU then you can buy a PSU tester from Maplin:

http://www.maplin.co.uk/search.aspx?MenuNo=12140&MenuName=PSU+Tester&worldid=-3&FromMenu=y&doy=10m10

Having said that, they're quite expensive and if the cooling fans don't come on then there's probably something wrong. Have you checked the fuse in the kettle lead which connects your PSU to the mains?

the box had the processor fan unit, and a small rectangle metal pad which i assume is the processor, or is that the pad your on about?If you used the boxed cooler which came with your CPU then there was almost certainly some thermal interface material already on the heatsink (it looks like a small square of Blu-Tack on the bottom of the heatsink)...if so, you don't need any extra thermal grease.

I don't mean to sound rude, but if you don't know what a processor looks like, are you sure you should be building your own rig? I must say your posts don't inspire confidence!

Laffertytig
10-10-07, 09:05 AM
haha yeah im no expert but i built my last rig last year and had no probs.

on the MB where the processor goes a lever lifts, the instructions said to place the seperate rectangle pad on the motherboard, then the fan unit on top it then secure. is that rectanglar pad the processor, or is that the thermal pad?

so the old PSU fan should start up when plugged into the mains? it didnt, and i used another socket

the power lead i use to the mains has a 5 watt fuse, is it possile that because i have a more powerfull PSU its blown the fuse and i need a more power fuse or something?

SUBMAN1
10-10-07, 09:09 AM
Two things off the top of my head-

1. Get some Arctic Silver and DO NOT TRY TO TURN YOUR SYSTEM ON WITHOUT THERMAL GREASE!!! Put the Arctic Silver between your cooler and your CPU. If there is no contact mechnism, you will have very inefficient heat transfer and you will eventually make yourself an expensive paper weight out of your CPU because of it.It will litterally burn itself up.

2. To check your PSU, unplug your video card from the system and check if it powers on. That PSU you showed may have wattage, but may not have enough amperage on the +12 volt to kick the system on with the video card in the system. If the system turns on without the video card in the system, your PSU does not have enough power.

-S

Laffertytig
10-10-07, 09:21 AM
so just to get things straight, the pad i placed on the MOBO IS the processor then, and the other item thats placed on top is the fan unit? i seem to recall the athlon 64 processor i installed last year already had paste on it. shouldnt this paste be supplied with the unit?

il try your 2nd point when i get home as im using my work pc right now. last year i had a laptop so i was online gettin help as i was building it but this im on my own building it

3Jane
10-10-07, 09:26 AM
Not sure if this is the same issue. But a while ago I had something similar to a new machine I had put together. It turned out to be simply that the 'kettle' mains power lead was not quite making full contact with the p.c power-source. This lead had been in use before, but I was using a new power-source with a fractionaly smaller socket. If your system had run for a while then shut down, that would indicate a temperature issue, but that doesn't seem to be the case. You still need thermal paste though :o.

Laffertytig
10-10-07, 09:32 AM
so u reckon it could be as simple as the lead then eh?

SUBMAN1
10-10-07, 09:36 AM
so just to get things straight, the pad i placed on the MOBO IS the processor then, and the other item thats placed on top is the fan unit? i seem to recall the athlon 64 processor i installed last year already had paste on it. shouldnt this paste be supplied with the unit?

il try your 2nd point when i get home as im using my work pc right now. last year i had a laptop so i was online gettin help as i was building it but this im on my own building it

If you did have a thermal tape on your CPU cooler, then you should be OK. Its not as efficient as something like Arctic Silver, but it will do the job.

-S

SUBMAN1
10-10-07, 09:38 AM
so u reckon it could be as simple as the lead then eh?

He is right. I've had a PC or two not turn on because of the power connectors not being seated fully. It is something else to try.

It could be that you have a bum MB too. Or maybe hooked up the power button leads wrong. Could be a number of things.

-S

3Jane
10-10-07, 09:59 AM
Maybe, do you have another power-source you could use. Just to see if it's your new PS or something else.

Prof
10-10-07, 10:09 AM
haha yeah im no expert but i built my last rig last year and had no probs.

on the MB where the processor goes a lever lifts, the instructions said to place the seperate rectangle pad on the motherboard, then the fan unit on top it then secure. is that rectanglar pad the processor, or is that the thermal pad?That would be the processor :) The thermal pad (if it had one) would be a small square of grey squidgy stuff stuck to the bottom of the heatsink (the big metal lump with fins and a fan on top).

so the old PSU fan should start up when plugged into the mains? it didnt, and i used another socketI've just realised that I've been talking nonsense! Sorry. Of course the fan won't start when it's not plugged into the motherboard! I don't know what I was thinking! Make sure you've got the power switch plugged into the right connectors on your motherboard. It's worth checking the manufacturer's website to see if there was a mistake in the manual. I've built a system (many years ago) where the printing on the motherboard, the manual AND the 'correction' to the manual were ALL wrong about where to put the power switch!

the power lead i use to the mains has a 5 watt fuse, is it possile that because i have a more powerfull PSU its blown the fuse and i need a more power fuse or something?I can't imagine your PSU drawing more than 5 Amps (not Watts!) from the mains unless it's broken. Still, it's worth trying a different fuse (or a different lead if you don't have a spare 5A fuse handy).

I've had a look at your system specs and you have built a high-end system powered by a very cheap PSU. Big mistake, if you ask me. A decent system will need a decent PSU to run properly. Although it might say 550W on the case, it might not be able to supply enough power on the 12V rail to power your GFX card.

Still, I would have thought it would at least turn on!

SUBMAN1
10-10-07, 10:23 AM
I can't imagine your PSU drawing more than 5 Amps (not Watts!) from the mains unless it's broken. Still, it's worth trying a different fuse (or a different lead if you don't have a spare 5A fuse handy).

I've had a look at your system specs and you have built a high-end system powered by a very cheap PSU. Big mistake, if you ask me. A decent system will need a decent PSU to run properly. Although it might say 550W on the case, it might not be able to supply enough power on the 12V rail to power your GFX card.

Still, I would have thought it would at least turn on!Nope, you will get 0 life if the PSU is not able to power the system. It will refuse to turn on at all.

By the way, my PSU has a 55 Amp inrush voltage, so I have popped 15 Amp circuit breakers on occasion for simply plugging my system into the wall! :D In my old place, I never dared unplug it since it was a pain to keep resetting the house circuit breakers until the inrush voltage was finished.

-S

FIREWALL
10-10-07, 10:28 AM
I didn't notice anyone else ask.

But, have you been wearing a ground strap or a least been grounded to case during the assembly ?

God I hope so.

Prof
10-10-07, 10:52 AM
I can't imagine your PSU drawing more than 5 Amps (not Watts!) from the mains unless it's broken. Still, it's worth trying a different fuse (or a different lead if you don't have a spare 5A fuse handy).

I've had a look at your system specs and you have built a high-end system powered by a very cheap PSU. Big mistake, if you ask me. A decent system will need a decent PSU to run properly. Although it might say 550W on the case, it might not be able to supply enough power on the 12V rail to power your GFX card.

Still, I would have thought it would at least turn on!Nope, you will get 0 life if the PSU is not able to power the system. It will refuse to turn on at all.Interesting...I would have thought that the current draw from the GFX card on start-up would have been small enough that the problem would only be apparent when the GFX card started drawing peak current (i.e. when running a 3D game).

By the way, my PSU has a 55 Amp inrush voltage, so I have popped 15 Amp circuit breakers on occasion for simply plugging my system into the wall! :D In my old place, I never dared unplug it since it was a pain to keep resetting the house circuit breakers until the inrush voltage was finished.I believe you, but I can say I've never had any such problems on any of my systems using standard 13A fuses and breakers. 55A is crazy!

SUBMAN1
10-10-07, 10:53 AM
I didn't notice anyone else ask.

But, have you been wearing a ground strap or a least been grounded to case during the assembly ?

God I hope so.
I can happily report that I tried one back in 1993 as a fasion statement (actually, was helping out a PC builder at the time for the day) - for about 2 minutes, before I ripped it off! Before and since then, I have never owned a ground strap and have yet to fry a PC component - in all the 10's of thousands of components I have touched (used to be in the PC biz for a while way back when), nor any of the 20+ PC's I have owned over the years.

Don't get me wrong, its good prevention against not thinking about grounding yourself out before touching things (simply touch the case of the PC you are working on, or if it is external components, work on top of an anti-static bag), but not neccesary after it becomes common practice to automatically grounding yourself prior to working.

Though possible, I think it would actually be hard to really fry a component with static electricity.

-S

geetrue
10-10-07, 11:33 AM
I hope you get it fixed when you get home ... sounds like no power to the MB to me. Like the others said a loose plug can be the problem especially on the back of the power supply itself.

Here's a problem I had one time, hope it saves you or someone a trip to the computer store ... the sata plug on the MB to the hard drive should never be messed with while the power supply is plugged in.

Blew my power supply just trying to see if the sata was plugged in properly ...

I know, I know never put your hands inside a computer when it's plugged in, but I did ... I thought it was safe due to the whole unit was turned off. Power is still flowing through the MB to all of it's little plug in's.

Good luck mate

FIREWALL
10-10-07, 11:43 AM
Hi SUBMAN1

I don't use a strap either but I also have experience.

But I think your last statement was very dangerous.

To the inexperienced that could very costly.

Static damage is the most common cause of computer hardware failure
and not covered under warrenty and is easy to tell.

Our friend doesn't seemed to be all that experienced pointing out no thermal paste and doesn't know what a multimeter is or how to use it.

It's one thing if your talking to a peer and quite another to someone with
less experience who might be trying to wing it on their own.

Anywho it is probably a moot point. We'll never know if he fryed something.

I hope him the best of luck as I'm sure you all do.

SUBMAN1
10-10-07, 12:34 PM
Hi SUBMAN1

I don't use a strap either but I also have experience.

But I think your last statement was very dangerous.

To the inexperienced that could very costly.

Static damage is the most common cause of computer hardware failure
and not covered under warrenty and is easy to tell.

Our friend doesn't seemed to be all that experienced pointing out no thermal paste and doesn't know what a multimeter is or how to use it.

It's one thing if your talking to a peer and quite another to someone with
less experience who might be trying to wing it on their own.

Anywho it is probably a moot point. We'll never know if he fryed something.

I hope him the best of luck as I'm sure you all do.
That is why I emphasized that it is good prevention. Or maybe did I not emphasize that enough?

By the way, it is easy to return static killed parts. It is hard for them to tell too. They just think a transistor failed in the silicon. Replaced under warranty.

-S

SUBMAN1
10-10-07, 12:45 PM
I believe you, but I can say I've never had any such problems on any of my systems using standard 13A fuses and breakers. 55A is crazy!
Yep -it is crazy. I did a double take when I read that, and it explained my circuit breaker popping - and the need to reset it. I thought it had a short at first.

This is the PSU in question:
http://www.silverstonetek.com/products/p_contents.php?pno=st60f&area=

It is on page 1 of the manual - http://www.silverstonetek.com/downloads/st60fmanual.pdf

Looks like I was wrong! Only 50 Amps! (only) :D

-S

PS. A thought just occured to me - the inrush voltage of the video board is going to be high as well - the reason the protection of the PSU kicks in and the reason for the lack of power to the whole system for it.

3Jane
10-10-07, 01:02 PM
Just thought of something else. Make absolutely sure that the MB and CPU power connectors are firmly placed in their sockets. If they are even slightly misaligned the connection won't be complete.

bradclark1
10-10-07, 02:00 PM
Take it to a computer repair place and have them look at it. It's better to pay a diagnostic price than have to rebuy expensive hardware because you burned it.

SUBMAN1
10-10-07, 02:14 PM
Take it to a computer repair place and have them look at it. It's better to pay a diagnostic price than have to rebuy expensive hardware because you burned it.Well, I don't agree with this idea at least. This is no way to learn.

-S

bradclark1
10-10-07, 02:43 PM
Take it to a computer repair place and have them look at it. It's better to pay a diagnostic price than have to rebuy expensive hardware because you burned it.Well, I don't agree with this idea at least. This is no way to learn.

-SExpensive mistakes suck unless you can afford it.

SUBMAN1
10-10-07, 02:48 PM
Expensive mistakes suck unless you can afford it.They still suck just as bad even when you can afford it. I don't care if I rack in 10 digits a year, I will still get ticked at $100 mistake. :D

Anyway, to learn is actually more important that that $100. Eventually, you become an expert, and it can't make you many many times over that amount for your learned services. Look at the problem as an asset, instead of a liability is all I am saying since I don't think he will screw his system up, but he will definitely learn from the ordeal.

-S

FIREWALL
10-10-07, 05:07 PM
Sometimes the best thing to do is step back take a breather and then go back with a fresh out look and take it all apart and start over with the new advice and tips and VERY carefully put it back together double checking everything. Then cross your fingers and push the on button.:)

I read your posts very closely and you had help building his last rig.
I would suggest you do so again. It will be alot cheaper and a learning experience.

If you want experience take your old rig apart and put it back together
yourself with NO help and see if it works. If it does then youv'e gained knowledge and skills at minimul cost risk.

Again I wish you success :up:

sonar732
10-10-07, 08:44 PM
Have you tried the paperclip PSU test?


*** MAKE SURE THE POWER SUPPLY IS UNPLUGGED FIRST *** Simply Jumper Pin 14 ( which is the green wire) to any of the ground pins which are 3,5,7,13,15,16,17 ( all which have a black wire). I use a paperclip to do so, just stick the paperclip into the connector like you would be pluging it into the motherboard.

In my shop we had an LED connected to two wires via this method. Not only did the fan turn on, but the light did also.

Laffertytig
10-11-07, 03:18 AM
firstly, the cpu already has thermal paste so no worries there. still no joy with the power though.
heres what ive tried

pc case to MOBO wiring - on the case i have a "power sw" lead which has 2 holes. a "pow led -" and a "power lead +" both single hole. on the MOBO ive tryed pluggin these into the relevant pins to no avail. i reckon ive tried everythin with these wires
on the old asrock MOBO there was only 1 "power switch" lead which plugged into the "power button" socket which was a lot simpler.
i managed to wire up the old equipment in an older case no prob but no so with this new stuff.


someone said to try it without the vid card but no joy there either. the PSU has 4 cables and all are defo pluggle in the right place.
the tower is around 3 years old could the wiring in the actual case be the problem?

THE_MASK
10-11-07, 05:47 AM
Maybe take everything apart and start over . You have turned the on/off button to on at the back of the tower havnt you .

Laffertytig
10-11-07, 06:00 AM
haha yeah mate i aint no expert but i do know how to switch on a pc

bradclark1
10-11-07, 08:41 AM
sober is President of the slow learners association inc. :D

Laffertytig
10-11-07, 09:14 AM
i congragulate him on his post:) im led to believe the problem is that my PSU is of the cheap variety. whats power wattage would people recommend for my system?

the graphics card box recommends 750w or 400 minimum but others have said thats overkill

FIREWALL
10-11-07, 12:17 PM
That vid card will want power and lots of it.

I myself use an ULTRA X Connect 2. 550 W gets rid of all that ugly wireing. Check it out. $100.00

geetrue
10-11-07, 12:57 PM
Have you tried the paperclip PSU test?


*** MAKE SURE THE POWER SUPPLY IS UNPLUGGED FIRST *** Simply Jumper Pin 14 ( which is the green wire) to any of the ground pins which are 3,5,7,13,15,16,17 ( all which have a black wire). I use a paperclip to do so, just stick the paperclip into the connector like you would be pluging it into the motherboard.

In my shop we had an LED connected to two wires via this method. Not only did the fan turn on, but the light did also.

You didn't learn this in the US Navy old friend ... short cuts are not allowed, uh?

Have you ever had the pleasure of touching a three foot tall capacitor for the BQS 4 to discharge it for maintence?

Don't forget to use the proper methods are they will carry your chared body out of there.

FIREWALL
10-18-07, 10:30 PM
I guess this THREAD is DEAD.:rotfl:

Hakahura
10-19-07, 10:08 AM
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