Flash Memory Speeds? (CF & SD cards)
I want to buy some more memory for my PDA (iPaq 2215). I've noticed some differences in performance when using the different sticks that I have. I figured I'd do a bit of testing with what I have, before I buy any more.
1 x SanDisk 256MB CF card
1 x SanDisk 256MB SD card
2 x HP 256MB SD card
I want to go with SD (the iPaq has SD and CF slot), because my other accessories (WiFi card, modem) are CF. I need to have available memory space on SD when I use them. Plus I have a camera that uses SD card. But, I would consider buying CF, if performance is better. I do already have 768MB of SD memory.
On to the testing.
First of all, let me say that using M$ ActveSync to transfer files to the iPaq while it's on the cradle, is out. It is so freaking slow, it's unreal. I thought that I had a problem, but from searching the net I found that M$ has convinced everyone that this is as good as it gets. So, you absolutely need a card reader to transfer any large files. I bought a SanDisk ImageMate 8n1 reader.
Here is the raw data that I came up with. The reads/writes are in seconds, and were done with a 232MB .wmv file (the movie Apocalypse Now). The Sandra 2002 benchmark is a score in kB/sec, and was done with that same file on each card.
I created an Excel file with graphs, you can get it here if you want to look at it.
Basically what I see is, the HP SD cards are they best for me. What is confusing is that the SanDisk SD card was the worst. I figured that one technology (SD or CF) would beat the other. Then I'd expect to see small speed differences between brands. But my data was pretty confusing. I repeated most of the tests 3+ times, and everytime got nearly identical results.
I figured I'd throw this stuff at you guys, to see if anyone can make sense of it. Or at least I might get some others as confused as me. :D