Vodka freezes at a colder temperature than water, and also boils at a lower temperature than water. You could use this to your advantage if you set things up right. Freon boils at room temperature and is an excellent substance for moving heat around. You get your most significant cooling when the liquid boils (or evaporates). It takes more energy to move water from 99-101 degrees Celsius than it does to go from 59-61 degrees Celsius. That's because water boils at 100 and it's undergoing a transformation from liquid to gaseous phase. That takes a lot of energy to accomplish.
But based on your vague clues you're dropping, it sounds like you simply plan to submerge your Sempron in a big bucket of alcohol. This is the exact opposite of what THG did. They submerged the PC in a vat of oil. Oil boils at a much higher temperature than water. If you use vodka or any other type of alcohol, it will probably evaporate quickly unless sealed, then you lose the thermal benefits of evaporation.
This is all assuming vodka doesn't conduct electricity. I won't assume that. Go to Radio Shack and get a multitester. Test the conductivity of vodka and other alcohols. Also try adding a small amount of salt to the alcohol solution. Test that too. It's important. Here's why.
Most people think water conducts electricity. But that's not true. Pure water is a very very poor substance for conducting electricity. However, if you're in the water, it suddenly becomes a very good conductor. Why? Because the sweat on your skin has salt on it and the salt is enough to change the properties of the water. You will get electrocuted in the bathtub if the hair dryer falls in.
Let us assume that when you worked on the computer before, you left trace amounts of sweat (salt) on the computer parts. Let us further assume that the water component of the sweat has long since evaporated but the salt remains. If you add something that can use salt to become highly conductive, you will fry your components.