If you opt to replace the I/O board, be aware, the Defender pinouts are upside down from the Stargate and later I/O boards.
You can buy a later I/O card and use it with the Defender if you flip the connectors over and jam them on backwards. Or let me know. I recently built an adapter for another KLOVer, I could price one out for you if you don't want to build one for yourself.
I'm only mentioning it because Defender I/O boards are getting to be a somewhat hard to find commodity and if you can use a later I/O board, you can find them a lot easier and more cheaply. Plus about half the I/O cards identified as Defender I/O cards on ePay aren't Defender cards.
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