So for most DELL machines it's possible to access/control proprietary components using an uniform interface. So DELLDIAG has an uniform top interface to the host (proprietary) and on the bottom interfaces with ODMs implementation including the EC (and fan control). DELLDIAG - their own system for diagnosing, monitoring and controlling the computer. But DELL has its own requirements and adds something to that design. It's very hard to determine particular implementation and EC registers and their meaning. This means that there's no universal method to control all such systems. Now, every notebook/model is designed using different concepts from different ODMs. The point is that on both of them you can control the fans using the same method This means esentially, that the Host-EC interface and EC RAM layout (which you check/modify in RW-Everything) is very similar. So for example you can have a Toshiba notebook and an Alienware/DELL notebook which both were designed by the same ODM (e.g. Now we come to the point - usually parts developed by a particular ODM (including EC firmware) follow their own internal design and thus work similar for several platforms. They design the core and add DELL-specific requirements. So even in case of DELL, this part can be designed by Quanta, Compal, etc. It's a proprietary piece of system and is usually developed by ODMs. The important thing is the program that this EC runs (firmware). Which EC chip is used on a particular system doesn't matter much in terms of fan control. I suppose the IT8518E is just one of several dozens of different Embedded Controllers (EC). Let me start from beginning and since you seem to have technical background, I can go into details

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