Studio XPS 435T 9000 totally failed to boot

Turn on sys, heard soft continuous tone traced to XPS, and nothing on screen. Rebooted several times, same thing. Did internet search and one suggestion was the coin battery died. Good point, have never changed battery. Bought new batteries, open case, popped out old battery and I had got copper color on my fingers. Saw nothing on battery socket. Install new battery, rebooted, and got a display of items found on the PC and at the end, two suggestions to press F2 or F12 (not sure) one being to reset CMOS.

Finally found the mother board configuration and the component location 29 CMOS jumper location JBAT1 (Clr_CMOS). Also found on the internet to move the jumper from pins 2 & 3 to 1& 2 to reset the CMOS.  With a mag glass and lights located JBAT1 and pull out the jumper, then saw the three pins.

Now the new issue is I did not see nor remember which pins were 2 & 3.  Any suggestion on the pins or what may have crashed?

Running windows 10 for now. Will be moving to a Dell Windows 11 sys hopefully with 2 or more SATA drive bays, when I recover.

Also just replace another XPS with a Windows 11 ECT 1250.

Thanks.