Alcohol does leave behind residue .... 90% alcohol means 10% something else ..... it's very good, but it's not the best. I used to use 99% alcohol which ran me about $16 a bottle (90% is only $2.50) and was gone quickly as other peeps in the house would use for other things ..... three teenage boys scared on acne for example
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.... car dashboards, computer screens, KBs and mice ....etc
Indigo Extreme Cleaner is half the price for just a an ounce or so but it sits in my toolbox and nobody touches it
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..... I apply with foam Q-Tips covered in cheesecloth but so far the ounce is about 1/3 gone thru about 11 blocks / HSs so far....that's 6 CPUs and 4 GPUs and a MoBo Block. And on the GPUs include the VRM, VRAM etc