Earlier today (22/11), TechPowerUp servers were hacked. The attacker gained access to the forums user database, the one which stores user information. Details such as usernames, hashed and salted passwords fell into the wrong hands. Thanks to GPGPU, the passwords are as good as compromised. We have undertaken a security review, and are mandating a password change for all users. Your old password will not work, click on "forgot password" link and follow the instructions to reset it. If you use the same password (as your old TPU password) elsewhere (other sites), change it to something completely different. We sincerely apologize for the inconvenience, and promise to improve our security infrastructure. If you no longer have access to the email account you used to register, please email email@example.com and mention your username, old e-mail, new e-mail and IP address you typically use to post on the forums.