VOGONS


First post, by 386SX

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Hi,
I'm trying some different 20pin power supply on a 24pin motherboard (supporting dual core intel / ddr2) leaving the last 4 pin of the mobo connector obviously open. I read somewhere that beside some heavy power requirements it should still boot so I used a 1,65ghz low power dual core cpu but no way, the fan seems to move a bit and then it stops.
Do you think I still need a 24pin power supply or I can use these P4 20pin ones anyway? Or I need the converter cable?
Thank

Reply 6 of 9, by .legaCy

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The 4 pin power connector that sits right next to the cpu is connected right?
Just to be sure that is connected properly you can wiggle it in a little bit.
Is there anything that may cause short circuits like those metal stand offs in the case?

Reply 7 of 9, by 386SX

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.legaCy wrote:

The 4 pin power connector that sits right next to the cpu is connected right?
Just to be sure that is connected properly you can wiggle it in a little bit.
Is there anything that may cause short circuits like those metal stand offs in the case?

The connector is stable and the mobo is outside the case with just the cpu and ram. Maybe some components failed and causing this?

Reply 8 of 9, by SW-SSG

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It does sound like something on the board is shorted.

Without the 4-pin ATX12V attached, it should power on (fans spinning and etc) but not POST... at least in my experience.

Reply 9 of 9, by .legaCy

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386SX wrote:
.legaCy wrote:

The 4 pin power connector that sits right next to the cpu is connected right?
Just to be sure that is connected properly you can wiggle it in a little bit.
Is there anything that may cause short circuits like those metal stand offs in the case?

The connector is stable and the mobo is outside the case with just the cpu and ram. Maybe some components failed and causing this?

Well maybe failing mosfets or mosfet drivers, if you can diagnose the vrm part of the board.
This happened to me twice, one was a shorted motherboard(thankfully the psu protection prevented the motherboard to be fried, removing the short brought it back) and other was bad fets on the board.