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I boret a power supply for my new PC, I yet conect my new case. to try the new fan, whit out my motherboar, but nathing apen, no ligth no fan, do you thing my power is bad o sure I have to conetc to my boar?

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The simplest would be to connect the power supply to a motherboard since this is where the on/off switch is also connected. The power supply needs to be triggered on before it will operate. Plugging in power from the mains is not enough.

Alternately in most PC power supplies, you can try force triggering to turn it on with just your fan and lights connected. This is done by shorting the Green (or Gray in some) wire to the GND (black) wire on the biggest connector.

In most modern power supply designs, it needs a load across the +5V rail (latch on) to operate otherwise it will power on but then immediately switch off when it senses that there is no load connected. Sometimes this can be defeated by shorting the Orange (Power Good) wire to the Red (+5) wire.

A word of caution, some old Dell power supply as well as a few other brands do not follow the standard wiring color coding

Hope that this be of some help/idea. Pls post back how things worked out or should you need additional information.

Good luck and kind regards.

Hope that

Posted on Dec 08, 2007

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A good PC power supply has "power factor correction" and brings the power factor to nearly 1.0.
A 1000VA UPS can support 900V or more load.
A cheaper PC power supply without "power factor correction" will draw more current. A 1000VA UPS can only support about 600W load.

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Computer wont start, despite all components working, cpu looks corroded


Usually you diagnose these by process of elimination. Get down to the bare bone mobo without anything but the processor, good RAM (switch out if you can with different ones), and Power Supply. Eliminate everything else, no cd, no floppy, no hdd, no video cards, no sound cards, no cards at all really.

More than likely it's a bad power supply. Take the power supply to your local computer shop and they should test it for you for free... don't let them charge you for it. If it's good then test the cpu.

Hope this helps :)

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My PC is geting switch off when Power flatcutations come,even ups is connected and no back up comes from UPS, after that UPS takes >4 seconds to switch to mains supply.

A four second transfer time is way too long by at least an order of magnitude. There is no way the power supply in a PC can maintain for that long a time.

If you are in a real critical environment I would recommend going to a UPS which runs continuously and runs off a battery which is charged whenever utility power is available. That way there is no transfer time.
These offline units are harder to find however.

I suspect your UPS system is defective.

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My ups cannot give backup when AC power fails no power supplied to PC then PC is restarted but i replaced a new battery but no result found. What is the solution for this problem ?

It sounds like you have a computer with an Active PFC (Power Factor Correction) Power Supply.

Back-UPS units, when running on battery power, output a Modulated / Stepped Sign Wave. Active PFC Power Supplies are NOT compatible with this pseudo-sign wave power, which is the reason it will not stay running.

You need a Smart-UPS unit, capable of delivering a true sign wave when on battery output.

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Our computer shuts and turns itself on repeatedly with out any warnings.

Is it old or screwed up? the fan that cools the CPU (processor) could be broken and it just gets really hot and it turns off the make sure your computer is not fryed take it to some compouter guy that knows what theyre doing and have then check on it

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My ups battery backup time is too short even i replace the battery

sounds like you have too many devices plugged in, it's not the ups that's failing it's the amount of power it takes to keep all you devices running. you may want to buy a larger ups or you can unplug some of the devices you don't need in the event of power outage. if it's just your pc your power supply might be sucking up alot of juice, i'd check and see what the power consumption rate is on that particular power supply.

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Computer resets with Power cuts not always although UPS supplied

ups may not be true on line, type so sometimes when power outage happens there can be a very small break in supply. this can cause load items to shut down
get good quality on line ups.

Jun 02, 2009 | UPS Battery Backup Systems

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How hard is it to replace transformer in a desktop pcu?

It's not, It usually only require you to disconnect all connectors (Hard drive, motherboard, CD player) 4 screws out (around the fan grid), take out the power supply, then put the new one in place, put the 4 screws back and connect your new power supply to the same places, just be careful (don't touch the electronics component as you could damage them with static electricity) and it's a piece of cake


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Battery back up supply

it is possible that the fuse for the input of power is broken or bad

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To High tempreture

COMPLETELY unplug your computer before attempting this:

You need to remove the computer casing, usually there are screws in the rear of the unit, or some units have the sides that slide off.... Get a can of Air, and some cue-tips, and clean out your fan for both the power supply, your processor, and any other fan inside of the unit... Get rid of all that dust. This should be done maybe once every few months at least. Yes, get rid of ALL the dust... be sure to be careful while doing this, do not want u to damage the computer>.<

There's more if that doesnt work, but I'm not sure how technically sound you are, so I don't want to throw too much at you all at once :-) Lemme kno if that works.

Jan 08, 2008 | UPS Battery Backup Systems

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