Hi My self built computer has developed a new problem. It won't turn on... sometimes. I push the start up button, and nothing happens. However, if I waggle the power lead then sometimes, it will start. Moreover - if I waggle the power lead (or even if I don't), then I push the button, then sometimes nothing happens... for a few minutes. After which, the computer starts itself. The odd thing is that once started, there is no question of it continuing - it hasn't subsequently turned itself off once. So - is there a "starter motor", which just needs a split-second of power? Potentially important information: a car crashed near our house a few weeks ago, which interrupted the power supply, but by making it "flicker" a lot. I was using the computer at the time, but stopped after I realised what was happening. However, it did cause the computer power to essentially be flicked on and off at a phenomenal rate for a few seconds. Is the answer a new PSU? Current model is a Q-TEC PSU 650W (has been working fine for 2 years) Thanks for your advice Tom

Could be the power switch, the circuit on which the computer is plugged, the power switch connection to the MOBO, or the PSU.

"Current model is a Q-TEC PSU 650W (has been working fine for 2 years)" I'm surprised it lasted 2 months! Q-TEC makes cheap, crappy PSUs & that particular model gets horrible reviews. Here's was Hexus.net had to say about it: "QTec's Triple Fan 650W is clearly a joke power supply. From the triplet of cooling fans that battle against each other to cool very little, to the supposed ratings that don't even add up to 650W...." "For its rediculously low cost, the QTec Triple Fan 650W can only be described as a clown's supply. Buy at your own peril and don't say we didn't warn you. The worst supply on test by quite some margin and a complete misadvertisement of capabilities, suckering people into a poor purchase." http://www.hexus.net/content/item.p...

I addition to what jam has said about your PS being an el-cheapo that is more likely to give you problems.... "Potentially important information: a car crashed near our house a few weeks ago, which interrupted the power supply, but by making it "flicker" a lot. I was using the computer at the time, but stopped after I realised what was happening. However, it did cause the computer power to essentially be flicked on and off at a phenomenal rate for a few seconds." If you do not have everything that is plugged into AC power that is connected to your computer protected with a decent anti-power surge/spike protection device, that power fluctuation you experienced can damage any power supply. You could try removing the power to your case and making sure all the connections in your case are not loose, especially those from the power supply, and try removing/re-seating the ram and the cards, but the power supply is probably damaged and is now defective. You could see this, but the damage from power spikes or surges is often hard or impossible to see via physical evidence. Check your PS. See response 4 in this: http://www.computing.net/hardware/w...

Did you try another power lead? DerekW

Thanks all When I bought the bits to build this, I gave no thought whatsoever to the PSU - just bought what the salesman recommended. A mistake I won't make again. This may be a second rate unit, but the guy certainly charged me a first-rate price for it. I guess thats what happens when you don't research everything. The computer is plugged into a multi-socket board which claims to protect from surges. I've tried moving the plug around, and tried different leads. No difference. I'll get a new PSU as soon as possible. That Hexus review is fantastic. If anyone has any recommendations, then please let me know! Thanks all Tom

Thanks again for that Hexus review. Just wanted to close this subject off by saying that I bought the Akasa 650W PSU, and the difference is amazing. Its very nearly silent, took about 4 minutes to install (the wires are cased beautifully) and worked straight away without any fuss whatsoever. In defence of the piece of cr@p I've just removed (the Q-Tec Triple fan) it has managed to keep working for the last 2 years. That said, I have had lots of odd/irregular problems which I couldn't pin down to any particular component which are (hopefully) related to that alone. This has been an education. I would never have guessed just how important the PSU is. Tom