Cisco DPC-EPC3208 VoIP Cable Modem - Changing MAC Address and serial number


I need help changing the MAC Address and serial number of my Cisco Modem DPC-EPC3208. For me, only the internet connection is important. I don't use the VoIP connection/function on the device.

The modem was destroyed by a power supply overvoltage. The DC/DC converters IT7612M (see photos) are defective.

I bought a second used, identical and intact modem.

Since the devices are provisioned by my ISP with their MAC addresses and serial numbers, a replacement device cannot be operated without reprovisioning.

My idea is replacing the parts, where the MAC address and serial number are stored, from the intact to the defective modem.

To do this, I would need to know in which parts these data are stored.
Could it be the SPI spansion FL064PIF (see the EPC3208G)? Or maybe there is more than one flash chip, one for the BIOS/firmware and one for the MAC and serial number?

I think, this option is more promising than changing the DC/DC converter, because the overvoltage may have destroyed even more parts (SMD parts).

What do you think about my plan?

Background of the story:
My ISP, Vodafone, wants to get rid of the old Cisco modems of their cable network and in case of a failure, customers only get a so-called Vodafone station (modem-router combination) as a replacement device, which I don't want for various reasons. This station doesn't work properly in many cases. Some honest employees of Vodafone told me that they receive many customer complaints about this device and advised me to keep the Cisco modem as long as possible. My cisco modem has been running fine for over 10 years.

thanks, halejok

Why don't you just ask your ISP about reprovisioning? Wouldn't that be the easiest way?
"Dear ISP, I have a new modem. Please update from $old_mac to $new_mac. Thanks."

I have my own FritzBox on Vodafone cable, and all it took to get my FB registered and working was one phonecall and 2 hours later everything was working.

No, the provisioning of own old Cisco modems is often refused by vodafone employees. It's a matter of luck if they do.
The reason given is that these devices no longer meet the requirements of the current interface description (>

Given that you seem to be talking about vodafone germany, you should profit from the laws about Routerfreiheit (§ 45d Abs. 1 S. 2 TKG). Meaning that you are allowed to provide your own modem, as long as it meets your ISPs interface description (that might rule out the Cisco DPC-EPC3208, but other Euro DOCSIS 3.1 modems should be supported).

Yes, it's about Vodafone Germany, more precisely about Vodafone West (formerly Unitymedia).
I'm aware of the legal situation.
As I already wrote, the ISP doesn't allow the old Cisco modems to be connected as a own device due to the interface description (although there are probably a large number of customers who still use the identical Cisco modem as a rental device provided by Vodafone).

The range of purchasable cable modems or cable modem/routers on the market and permitted by Vodafone is currently very limited.

But in the meantime I was lucky enough that my second, intact Cisco modem was provisioned by Vodafone.
The "trick" is that you have to tell the vodafone employees that you want to register a FRITZ!Box.

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