Re: New psu - no power to system.

tom wrote: 
Thanks to both of you for getting back to me.

The voltage is set to 230V (I live in the UK, so this is correct)
There is a power switch on the back, it is set to the on position. I tried in both the on and off positions in case the switch was labelled incorrectly.

Is there a maximum wattage that can be connected to a motherboard? The reason I ask is because both PSUs are the same brand, but the new one is a more powerful model and output is the only obvious difference between the two PSUs.

Thanks
Tom

"hdrdtd" <hdrdtd@xxxxxxxxxxx> wrote in message news:F8adncF9Yvk1hVneRVn-pg@xxxxxxxxxxxxxxx

also, look on the back of the PS. is there perhaps a little slide switch used to set the AC voltage?

If so, they are ususally shipped with it in the 115vac position, but I have heard of the switch being set to 220 or whatever rather than the needed 115vac setting.


"Ken" <user@xxxxxxxxxxxxxx> wrote in message news:gzUwf.243969$qk4.150171@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

tom wrote:

Hi there.

My power supply on my PC is overheating, so I decided to buy a new one.

I made sure that the one that I bought was ATX with 20pins and had the 4 pin connector for P4. It does. The only difference between the old one and the new one is that the new one is 450W and the old one was 300W. All of the cables and connectors are the same.

I disconnected the old PSU and installed the new one, everything is plugged in exactly as it was previously. I push the button on the front of the machine and nothing happens - no lights, no fans, no beeps, nada. I reconnect the old PSU, and it works (although it still overheats after an hour or so)

Have I been unlucky and been sold a faulty PSU, or is there something else I should try before I take it back?

Thanks.
Tom

Is there an on/off switch on the rear of the PS????




The wattage rating is the maximum that it can put out. Your computer and its components will draw what they need, and as long as it does not exceed the maximum, you will be OK. I would make sure your connections from the PS are secure and not reversed anywhere. If one were to somehow be reversed the PS would go into an over current condition and shut down immediately. Start with all accessories (HDs, CD drives, floppies, and anything else) NOT powered or attached to the MB. You are just interested in seeing some life on the monitor. Once it starts, add one component at a time.
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