I've done the RAM and SSD, and at a push, the battery looks straight forward enough and is essential too. As for the mhz.... not a clue.
I wonder if it would have just been enough to see the 16GB RAM with the HDD. Too late now, but would have been interesting. It's not bad, it's good enough, although when Snow Leopard was in, it was like lightning. And it's not quite that good with subsequent El Cap/Sierra/High Sierra. I get a lot of lag on Chrome, and sometimes Mail is painful. But for the age of it, that's good enough at the moment. And as discussed, the options on new don't excite me as much as they should, other than aesthetically, because there is more on what I have, options wise, and USB wise. I've lost the use of Photoshop with HS, and Word 11 is showing different fonts and acting weird, despite compatibility being ticked on roaring apps.
One thing I didn't do, and don't know if it was a mistake, was not to set up TRIM,
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