I ran HD Tune and everything is okay according to it but I get tons of "Packed Data CRC: Volume is corrupt" error when extracting rar files... also checked for bad sectors - there were none.
I tried changing a SATA cable but that didn't help.
What could be the problem?
Then try downloading another big archive (e.g. ZIP) and test this or download a Linux CD ISO-image for which a md5 hash exists and verify this. If one of the two suggestions works your problem has nothing to do with your drive oder other hardware. Even without this test the problem almost certainly has nothing to do with the drive. If the rar archives come from the same source perhaps all are corrupted, they use an incompatible version or the server is causing the trouble.
Lets say I download an archive with 48 rars, then every time I try to extract them, a few of them are corrupt, but whats strange is that the corrupt parts are different each times which means the rars themselves are not corrupt, and the drive is reading them incorrectly.
What could cause this?
If you downloaded them only once and get different errors each time you try to extract the files that changes everything. Perhaps you might try to use a seperate tool to verify the CRC32 od MD4. If the values change between two consecutive passes somthing is definitively wrong and I have no further ideas. Perhaps checking the system log files might reveal something unusual (e.g. Windows: Event Viewer => System).
I have another symptom of the "disease" -
when downloading through uTorrent, it usally finishes the download and then when I force a Re-Check not all files have even been completed, they're at 98% or 99%.
what the hell is this ***?