New PSU-Won't boot

alphanumeric · 25 Mar 2011

If you have all the power cables correctly connected, and nothing is damaged, it should boot up using the power button on the motherboard. Even with all the case cables disconnected, it might even be worth trying it with the case power button, reset button, etc cables disconnected, just in case one is in fact shorted out. The polarity of the case reset and power cables doesn't matter, but the hard drive LED and power LED cables have to be on the right way or the indicators won't light up.

johnwillyums · 25 Mar 2011

Anak. I don't seem to have the second one down, the ATX 12 volt. That's why I'm using the one from my previous psu. (yellow in the pic)
This is all I have left from the Corsair stash. All the rest are SATA cables.
The one in the first pic seems to have the correct profiles to fit into the ATX 12 volt socket top left on the mobo but the plug is too long to fit in the socket as there is something protruding from the mobo directly under it. As the 4 bottom pins are empty I suppose I could cut them off to make it fit and that would leave me with 2 4 pin sockets to go into the psu. That doesn't feel right.
Also, there's no reason why the old one I'm using shouldn't work. It fits perfectly.
I'm still thinking it's the front panel header pins as I had trouble with these before.

Dwarf · 25 Mar 2011

Hi John,

This is the cable you need. I take it that you have tried to fit it with the single plug end to the motherboard? That end should go to the PSU and the twin plugs should go to the motherboard. The cable is designed so that the same adapter can be used for motherboards requiring a 4-pin or an 8-pin connector. Quite why the single connector has unused positions, I'm not sure.

johnwillyums · 25 Mar 2011

Right. Got it. I'll try that. Very awkward to get those 2 plugs in, Thanks. Back in a minute

johnnya · 25 Mar 2011

Good call Dwarf. That cable is exactly what he needs. Some motherboards only have 1- 4 pin connector, while his apparently has two - side by side. And yes they can be a tough fit. Have to be careful of other components near by.

Dwarf · 25 Mar 2011

I've had a look on the Corsair forums regarding this PSU, and there are a number of entries regarding this connector. To me, it is just poor design.

The Corsair Support Forums - Search Results

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johnwillyums · 25 Mar 2011

Dwarf! You magical man:) I now have power, fans etc. hooray. I'm getting somewhere but still no boot or display. The mobo is showing number 69 in LEDs
Any ideas on that?

johnwillyums · 25 Mar 2011

Mobo manual say "turn on L2 cache". Anyone know how to do that?

Dwarf · 25 Mar 2011

I'll have a look, but I don't rate the Gigabyte website for its ease of use.

johnnya · 25 Mar 2011

If you Google "Turn on L2 cashe" you will get many hits. The one below still refers to possible POWER issues. ??????? This is getting stranger by the minute.

"Turn on L2 Cache" isn't an instruction to you, or anything that's optional on the system; it means that the BIOS got to the stage in the start-up routine where it was commanding the CPU to activate it's secondary on-die memory cache; this command could simply be failing due to a bad CPU, or it might be hanging there due to insufficient power delivery. The first thing I would do is re-seat the CPU - it might just be a poor contact ball...