Beginning yesterday, many PlayStation 3 owners have been unable to play games on their PS3 video game consoles and have been unable to access the on-line PlayStation Network.

The source of the problem is unknown, however, many gamers are pointing to the internal clock on older fat versions of the PS3.

Owners of the slim PS3 models are not said to be experiencing the problems.

Some Digital forum members say they have been able to play games offline by deactivating internet connectivity in system preferences; manually change the date on the PS3 and rebooting the system.

Sony is aware of the problem and posted the following message on Sunday on the official Playstation Blog. No updates have been provided by Sony as of 11am on Monday.

"We’re aware that many of you are having difficulty connecting to the PlayStation Network this evening. Those of you with 'slim' PS3s (the 120/250 GB models) appear to be unaffected. "

"Know that we have narrowed down the issue and have engineers working to restore service even as you read this. We apologize for any inconvenience this may cause you, and genuinely appreciate your patience while we work to resolve this."

Discuss in Digital Home's Video Gaming forum .