I built a new PC Last night and it started fine. I started the install of XP Pro and when I looked back at the machine it was dead. Tried to restart but no power. Specs are below:

Radeon 9800 XT
Sound Blaster Audigy Platinum
DFI LanParty 875B
2 512 DDR 400Mhz
2 120GB SATA drives
CDRW
1 200GB IDE Drive
3 Case Fans
Cathode Tube cooling light

Wondering what wattage of a power supply I should try next the one I had was a 450W

Hello, and welcome to the PC Guide. :)

Download a copy of my diagnostic flowcharts from here
www.erniek.eclipse.co.uk/downloads/sylvanderdiags.zip
and print them to leaf through.

Begin on the START UP chart.
You should then be taken to the SYSTEM chart.
The web links in note 1 will give some background information on dealing with an ATX Power Supply.
You may be directed to the ATX POWER SUPPLY chart.

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TESTING ATX POWER VOLTAGES

See this http://www.pcguide.com/vb/showthrea...=&threadid=8680
Then the below, here http://www.pcguide.com/vb/showthread.php?s=&postid=152496#post152496

Black = ground
Red = +5 volts
White = -5 volts
Yellow = +12 volts
Blue = -12 volts
Orange = +3.3 volts (?)
Green = power on

Turn the power on. The fans should at least come on so that you know you have power.

Turn on the voltmeter and set it to measure DC voltage. Start with an IDE power connector that is not used. Place the black lead of the voltmeter in the hole of the connector that has a black wire (ground). Connect the red lead of the voltmeter first to the yellow hole and then to the red hole. The voltmeter should read +12v and +5v respectively.

The other voltages may usually be measured at the motherboard power connector by simply sliding the red multimeter test probe down the hole where each colour wire goes (with the black probe connected to any black wire as before). Really you only need to check the orange wire for 3.3 volts at this connector. If +12, +5, and +3.3 volts are all okay, then your power supply is probably fine.

Unfortunately, a low voltage measured in this way may mean a bad PSU or that some other component (motherboard, etc.) has a short and is pulling the voltage down. Therefore, the main value of measuring voltages is to eliminate the PSU as a source of the problem (if it has normal voltages).
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Thanks a million. I have tried to measure the voltages and the PS is blown. I think I am going to try and use a more powerful power supply.

I have seen it said by someone who knows, that every PSU he has ever examined had a fuse fitted, so perhaps the in your PSU fuse has blown.

I've also seen it said that a 350W PSU is usually sufficient.

Are you sure you need more than 450W?

I have seen it said by someone who knows, that every PSU he has ever examined had a fuse fitted,

I think that was probably me, I have a dozen fuses on my bench from older and unneeded power supplies I've scrapped. Never seen one without a fuse, even the old IBM XT machines. (That's what several of the scrapped power supplies were.) Strangely enough, when power supplies get fried it's usually not the fuse though...I've only found one dead PSU with a blowen fuse, and replacing the fuse only resulted in another blown fuse...

Unless you plan to run two CD drives, two hard drives, zip drive, several USB devices, 4 or 5 fans, and professional grade video and sound cards, (think $700 sound cards etc, they can draw quite a load) then a 350 watter should handle the average system. You should only need to go to 400 or 450 if you're building a serious gaming machine with all the bells and whistles, high end video and 3 or 4 fans, maybe some neat lights...
Before you guys say no way - $700 for a sound card??? Scout around for what radio stations are using...$700 is a low end card...They can run over $1000 for high end full duplex broadcast quality cards. In that context, full duplex means play two full stereo tracks at once, from separate CD or software sources, to fade one song out and another in, all while the DJ talks. That's what radio stations use to record commercials, canned weather forecasts, traffic reports etc. Often when you hear 4 commercials in a row, it's one *.wav or *.mp3 file sitting on a hard drive on a networked workstation in another room.

About time someone came up with a staggered startup system for PC's.

I mean 350W is silly, the only time a system will ever draw anywhere near this load is on startup as everything lurches into action including the real heavy users all the systems motors drawing extra power as they struggle against inertia in a bid to get up to speed when they can finally relax on the power draw.

I mean nobody need their Hard/Floppy/CD/DVD etc drives in the first second or two of boot-up and the CD/DVD's can wait longer still. It's not beyond the realms of technology to stagger the startup sequence.

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