Memory: Inspiron 9300 taking XPS M1730's SO-DIMMS

So I have an Inspiron 9300 that's served me quite well since 2005. I recently bought an XPS M1730, and I made the smart decision of only purchasing the bare minimum of RAM (2GB).

I want to upgrade the XPS's memory to 4GB, and I plan on getting a couple of 2GB modules from newegg.

My question is, can I take the stock XPS M1730 memory and throw it into my old i9300 and expect it to work flawlessly? I figure they're the same 200-pin SO-DIMM modules, so they should be interchangeable (err--backwards compatible, that is).

On the subject of upgrading an Inspiron 9300, is there any CPU I could potentially upgrade it with? It's running on a Pentium M 740 (1733 MHz). My ideal use for this old laptop will be an HTPC of sorts--although I guess it will never be able to play back 1920x1200x30p content. Let me know if I'm wrong there!

 

It should work fine they both use DDR2 memory, the only thing that may happen is that the memory might down clock to 533Mhz since I believe that is the bus speed on the i9300 motherboard but I may be wrong, and the other thing to consider which I do not know the answer to is what is the maximum amount of memory that the motherboard supports on the i9300. But the XPS memory will work just fine on it otherwise. On the cpu upgrade, I am not sure what it supports and what you will find since it uses the old and outdated P4 architecture.