imac-promemory
I'm considering getting an iMac Pro. I'd love to max out the crazy amount of memory but beyond my budget. Thinking of getting 64 GB RAM. If I did want to upgrade after purchasing, would I need to get 3 more 64 GB units to fill it out or does it not work like that for this machine?
Note: I do understand that upgrading is not easy and I would take it to a certified place to get it upgraded – just hoping to save some $$$ this way.
RAM still is a lot faster than any SSD which you use in your Mac. RAM has a shorter access times and much higher transfer rates:
[table]
The SATA interface by which the hard disk is connected limits the throughput to a theoretical maximum of 6Gbit/s (600MB/s) for SATA3.
You can determine how much the page outs are written to the disk by taking a look at the Activity Monitor. I try to keep the ratio at a maximum of 10/1 (page in/page out). The more page outs you have, the more like a RAM upgrade will benefit you.
Your logic is sound. Just something to keep in mind is that while yes swap is much faster on a SSD, it is still much slower in respect to RAM and both should probably be upgraded. But yes she would see the most improvement by going to a SSD
Just as a side note 10.10.1 will try to pre-cache as many things as possible in RAM so apple uses 'memory pressure' to reflect the systems demand for RAM.
Best Answer
If you get the 64 GB option, then this would be four 16 GB units. Basically, Apple is going to ship the computer with the four memory slots balanced with the same memory size. So when you upgrade later, some (if not all) of the memory you paid extra for will be replaced.