Three dots on the upper right corner under the X.
Settings
Scroll down
Advanced Settings
Clear Browsing Data
Select only the box that says "Cached images and files"
And clear all that cache that's been saved up from various flash-based ads, facebook, reddit, etc.
Unlike Firefox or Opera or Safari, cache killers and disk cleaners don't tend to find Chrome's cache files, that I've found. You really have to manually dig in and clear it through Chrome itself to be sure it's gone. Antivirus is also really good at slowing down the caching and reading of cached files, the tradeoff you pay for the perception of security.