SSD + HDD in Macbook. QUESTION

[Miguel Palaviccini]

I upgraded to a SSD a while back and it has been awesome, to say the least. Computer loads programs much faster and I haven't had photoshop die on me with the large (36 MP) files of the D800.


However, I need more storage space than what I currently have available in my HDD (500 GB). I have 32 GB open - which is exactly the size of my CF memory card for my camera. Sad. I've been looking at upgrading to a new HDD and have found some options. I have some questions for you, but first some background:


- I am currently running all applications and OS from my SSD.
- All of my photos (and data) are on my HDD (Seagate Momentus XT 500 GB Hybrid Drive)
- So when I go to edit a photo, the program uses the SSD (and the scratch disk from that), but it talks to the HDD, where the photos/data are kept. Right?


Ok so now some questions regarding the upgrade of the HDD:
- Will there be a difference between 5400 and 7200 RPM? I know there would be one if it's the main drive, but it's not. So does it matter how fast it spins?
- Will there be a difference between 8, 16, and 32 MB of cache for my applications? My understanding is that the cache is used by the main drive running the applications (in my case the SSD).
- I know that if it were my main drive, all of these would be attractive features, but since all it does is store the information (which I understand needs to be read and written by the SDD), I'm not sure how important they are.


I'm not planning on getting a new computer for at least another year, and could really use this new hard drive soon (when I graduate!). I have found these three HDD that I think fit the bill:


- ($85) HGST Travelstar 1 TB 7200 RPM 32MB Cache
- ($80) Seagate Momentus 1 TB 5400 RPM 8MB Cache
- ($120) Seagate Momentus XT 1 TB 7200 RPM 64MB (which is the upgraded version of what I have now)


Let me know what you think. The price of the second one is at an all time low according to CamelCamelCamel (I've been following it for a couple of weeks now).

[Miguel Palaviccini]

I did find this about cache and external drives ... "Cache size refers to the speed of the external hard drive to copy the files from the source computer to it. As a general rule, the higher the cache size or memory of an external drive, the faster it transfers files from the source to the storage and vice versa. If transfer speed is of significance to you, then you might as well get one with a large cache size."

Makes me think that cache is more important than RPM?

[Don Lacy]

Hi Miguel, The transfere speed of the connection used has the greatest impact on an external drives performance.

[Miguel Palaviccini]

Thanks Don. I figured as much, and I know that the hardrive has a SATA 2 connection (3Gb/s), but I was wondering if that was the bottleneck. Meaning, will the RPM or Cache upgrade be noticeable?

[Don Lacy]

Thanks Don. I figured as much, and I know that the hardrive has a SATA 2 connection (3Gb/s), but I was wondering if that was the bottleneck. Meaning, will the RPM or Cache upgrade be noticeable?

I dont think so but I am far from an expert on the hardware side of using PS I have never seen any differance while working on images from my external or internal drives other then the time it takes PS to load the image once in the program all other functions are the same.