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Electronic Theatre Controls Inc

Where is the BIOS (CMOS) Battery on an Eos Classic?


This article will show you where to locate the BIOS battery on your Eos Classic motherboard. 


The information in this post is provided to assist in troubleshooting. Perform work at your own risk. ENSURE ANY POWER FROM DEVICES HAS BEEN DISCONNECTED BEFORE SERVICING ANY EQUIPMENT. If you do not feel comfortable performing the work, please contact us or your local service center. Be aware that ETC and its Affiliates are not responsible for any damage or injury caused by service of our products by anyone other than us or our authorized service providers, and such damage is excluded from the product’s warranty.


When replacing the BIOS battery in an Eos Classic, it is necessary to remove the back lid of the console. 

The BIOS battery is located on the motherboard and is populated on the board between the fan and the console's back USB porst. 


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