Update AVG is putting an emphasis on increased speed with a revamp of its free and paid for security suites.
The latest revamp - AVG 9.0 - boasts 50 per cent faster speed and increased ease of use. Improvements in speed have been achieved by skipping the scan of files already marked as safe in future scans unless the file structure changes. The approach also offers claimed improvements of ten to 15 per cent for boot times and memory usage, respectively.

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AVG goes toe to toe with MS in consumer security fight • The Register