IS7 + Enlight 420W Power Supply = Problem with 3.3V Rail?

[S0me1X]

'm currently using an Abit IS7 motherboard with an Enlight 420W power supply.

Recently, the 3.3V rail dropped significantly to ~3.10-3.20 (was 3.30-3.35 a couple of months ago) and I noticed that the 3.3V pin on the ATX connector of both the power supply and the motherboard seems to be burnt (the pins on the mobo are normally silvery, but the 3.3v one is darkened.) Can anyone tell me what I should do about this?

 

[Buz2b]

Originally posted by: S0me1X
'm currently using an Abit IS7 motherboard with an Enlight 420W power supply.

Recently, the 3.3V rail dropped significantly to ~3.10-3.20 (was 3.30-3.35 a couple of months ago) and I noticed that the 3.3V pin on the ATX connector of both the power supply and the motherboard seems to be burnt (the pins on the mobo are normally silvery, but the 3.3v one is darkened.) Can anyone tell me what I should do about this?

In a word, "RMA". The problem you have is defining the cause. Most likely the PSU but could also be the voltage regulation components on the MB. Most likely the PSU though. I'm not sure though as to what you are referring to when you say "the 3.3V pin on the ATX connector of both the power supply and the motherboard seems to be burnt ". Specifically, are you saying that the MB connector and the PSU cable/connector are showing "burned areas" and if so, are you sure that these are the 3.3v connections? Just curious.

It kind of sounds like maybe the MB plug wasn't secure and as it "wiggled" a bit it cause a short. That's one theory anyways.

 

[S0me1X]

The pinout of the 20-pin connector indicates that the burnt pin was the 3.3v. (The bottom left pin, if you look at the IS7 horizontally with the ATX connector closest to you.)

I can't RMA because the northbridge of the board fell off some time ago and I fixed a new northbridge heatsink on it using arctic alumina epoxy :-(

 

[o1die]

I tried that same power supply in a newegg refurb, but it was doa. You can rma the power supply direct to enlight. I wished I had known it earlier. I rma'd it to newegg, but they gave me a refund instead of replacing it.