That's rough, but it's probably not the RAM itself. Those tiny Optiplex cases are a nightmare for static. A lot of people forget to unplug the power cord and hit the power button to drain the board before touching anything. Even a little leftover charge can fry something when you're working in such a tight space. The pop and smoke points to a capacitor or a voltage regulator going, which a static zap could totally cause. Always worth double-checking you're grounded and the system is fully powered down, not just asleep.
My buddy Steve lost a whole gaming rig last year trying to swap a GPU. He swore he unplugged it, but the PSU switch was still on. Heard a snap from the motherboard the second the card made contact. Fried the PCIe slot and the new card. He was so mad he didn't touch a computer for a month. That pop and smoke smell is unforgettable, and it happens way faster than you'd think.