Only southbridge chipset is connected directly to the main 3.3v and 5v rails.
measure the resistance between standby 3.3v to the ground on pin no. 14 of any pci slot:

this is boardview for Asus A7n8x if you are interested in nforce 2 power rails.

open it with http://boardviewer.net/

Wait, ain't those pins A1 (test reset) and A14, reserved?
Still, 280-ish Ohms
There are still a few that are connected to both rails;
- Southbridge
- BIOS-rom(?)
surely something else too. Too bad I haven't found any schematics for the chaintech board 🙁

280 ohms is pretty good, so there's hope that southbridge is not toasted. I would start measuring the mosfets source and drains on those rails.

I put this on hold and ordered a thermal camera. Should assist me. I have not changed the caps yet.

I received the thermal camera today.
The ITE IT8702F-A was shorted to 5V and the southbridge (Nforce 2 MCP FB6269.1) is shorted to the 3,3V rail.
So that's that then. 400e for a thermal camera to tell me that a 20e board is practically unrepairable 😀

oh2ftu wrote on 2024-03-27, 14:28:

I received the thermal camera today.
The ITE IT8702F-A was shorted to 5V and the southbridge (Nforce 2 MCP FB6269.1) is shorted to the 3,3V rail.
So that's that then. 400e for a thermal camera to tell me that a 20e board is practically unrepairable 😀

You already spent 400, buy some chipquick and a microscope and fix that board! 🤣

Uhm... he might be slightly right on unrepairable. The few cases I've had ITE/Winbond chips burnt, when replaced they'd burn again. So my guess is either NB or SB gone that's subsequently causing the SIO chips to burn as well.

Yeah. The SB is shorted, and they seem quite hard to find. The SIO seems quite available, but not worth the effort without the SB. Changing a BGA is nothing new to me though.

Ok so just to verify; pulled the SB off -> the last shorts are gone.
They are available on aliexpress: https://www.aliexpress.com/item/1005006379447748.html
And the ITE is available on eBay: https://www.ebay.co.uk/itm/400080140446
I presume the ITE is not pin-compatible with a Winbond equivalent.
Still, those add up to 40-50e incl. taxes so I don't see any point in spending that kind of money on a Socket A -motherboard.

Even then it's not worth fixing - there's more sweet boards to fix that may be out there:
- MSI K7N2 Delta-ILSR
-ASUS A7N8X (though beware as the Deluxe has been nothing but pain for me. The -X version is sweet to work with.)
- Soltek 75FRN2-RL
- ABIT NF7
- Gigabyte 7N400 Pro2