In this article, I’ll upgrade a Philips CDI450 with 32 KB NVRAM. You’ll find all information that is needed to modify the system ROM and the mainboard. If this sounds familiar – yes, it does: In 2019, I explored the possibility to upgrade a CDI470. Even though patching the system ROM failed back then, the experiment was still a success. The final solution to access 32 KB NVRAM was to use the ROM of a 490. As it turned out later, this was also Philips’ solution for the 470/85 model, but that is a topic for another article.

With the 450 (and all other top-loading players with Roboco mainboard) it is a bit different: It’s a low-cost model with 8 KB NVRAM only. The mainboard was neither prepared for a bigger NVRAM solution nor is there a similar advanced model that I could borrow the system ROM from. This time, a ROM patch must succeed.