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Unable to run Pentium OverDrive processor at 486 Jetway J-437 motherboard.

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First post, by Susanin79

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Would like to run Pentium OverDrive CPU at my Jetway J-437 motherboard. (link to the Retroweb: https://theretroweb.com/motherboards/s/jetway-j-437) Unfortunately system didn't boot with the installed CPU at all.
For the first time I thought that the CPU is broken, all surface mounted components were removed, but the short circuit didn't disappeared. Then I received the advice from one forum member to check the 5V rail to shorts and indeed, it was shorted.
Closed inspection confirmed that some of the Vcc pins definitely sorted to the ground and some ground pins are connected to the 5v line. So I decided to remove any jumpers and continue to measure the shorts without them. You can see the tracing result on the picture. The blue circle mean that pin connected to the Ground and the red one means that pin is connected to the Voltage regulator.
Then I tried to trace the jumpers PINs and found that documentation didn't fit the jumpers on the motherboard. The group of jumpers marked as JT1 to JT7 has no full description. On the picture those jumpers were set for the DX4 CPU when I bought this board. And it looks from the trace information that JT2 and JT7 should be set to the 2-3 position to support PODP CPU.
With all this new information I thought that I found the cause of the issue, but not, the shorts still exist with the any of the jumpers configuration.
Would be appreciated for any advice.

Reply 1 of 3, by MikeSG

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I believe only the POD CPU uses those extra pins around the outside, and it will work without them inserted into the socket at all.

So if the motherboard manufacturer got it wrong by switching some of the VCC and VSS (GND), it's hard to think of a way to use the POD CPU on this board, except by removing the pins on the POD that don't match up...?

Reply 2 of 3, by Susanin79

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So many pins are affected, would like to keep the CPU. I can keep this motherboard as it is with the DX4 CPU.
I thought that if JT7 pin3 is connected to all GND PODP pis then this is a solution, but it didn't work. Will try to check the chipset legs connection, or that resistors pack.

Reply 3 of 3, by rmay635703

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Some early pod systems needed an interposer to run the pod because Intel F’d up the spec changing it at the last minute.

A simple socket 1 (486 socket) shoved into your motherboard and the p24t shoved into said commodity socket with the extra pins hanging might allow you to run the overdrive.

AKA there is evidence that the extra pins aren’t needed for operation, a few folks have upgraded original LIF socket 1 486 boards with a POD by simply giving it clearance to install with the extra pins NC

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