Seeking recommendation on memory cards

[Eowyn]

I'm currently looking to increase the storage on my IPAQ 2210. (from 256 on CF to say 1GB )

I intend to use the CF slot as my main storage for programs and files, because I have a SD WIFI card which I am using regularly (at home), but I am prepared to change my mind.

I'm guessing that CF II is faster than CF original.

Is there any practicaly/observable difference between SD and CF in speed, of accessing programs, and documents?

Do the larger capacity cards have slower speeds?

Or does it just come down to how much the wallet can bear?

[Menneisyys]

I'm guessing that CF II is faster than CF original.

Nope. Actually, most (but the largest, >=3-4G) flash-based CF cards are all CF I "only". Only Microdrives are CF II, but they have pretty poor price/performance ratio.

Is there any practicaly/observable difference between SD and CF in speed, of accessing programs, and documents?

In the 2210, not much: the SD is a BIT faster than the CF, even when a fast card is used in the latter slot and a standard SanDisk in the SD slot. The difference is not THAT big, anyway: I've benchmaked the 2210 and found only subtle differences. Some 500 kbytes/s versus 800 kbytes/s. If you need to access tons of files (e.g., digicam images), it can be very important to get a faster solution (meaning an SD card instead of CF's). A practical example: I've benchmarked all the available pic viewer/editor programs for my forthcoming article and found out that, for example, Resco Picture Viewer, while reading & rendering 12 5 Mpixel pictures in 31-32 secs off the CF card, has only spent 18 secs off the main memory and 26 secs off the SD card. This strongly corresponds to the file copying benchmarks published at http://www.firstloox.org/forums/showthread.php?t=2597 – that is, the PL720 accesses the SD card faster than the CF card. The iPAQ 2210 has similar results.

Do the larger capacity cards have slower speeds?

Nope.

Or does it just come down to how much the wallet can bear?

Yes. Just get a cheap card. It's pretty useless to get expensive cards for PDA-only usage because their high speed can sometimes be even contra-productive. The Belkin eFilm Pro cards are a perfect example of this: they have terrible writing speeds in PDA's. (See e.g. http://www.firstloox.org/forums/attachment.php?attachmentid=224 on this.)

You should also take account your other devices. If you have a digicam, for example, you could try to get the same type of card it uses (CF in most cases, except for some xD / MS / SD-based cameras) so that you can use the same card in both devices if you need to.

[Eowyn]

Thanks for the info, Menneisyys

My digital camera uses CF card, and I have on occasion put the camera's card in the PDA.

[Menneisyys]

Thanks for the info, Menneisyys

My digital camera uses CF card, and I have on occasion put the camera's card in the PDA.

Then, I think the best choice is getting a high-capacity (and hi-speed, assuming your digicam is a recent, non-low-end model - older/cheaper models aren't necessarily able to make use of the advanced speed of hi-speed cards), say, 1Gbyte/2Gbyte CF card (and, prolly, a low(er) capacity SD card to e.g. store your programs / PIE cache / mails on, just to have a "system" card in to save your PDA's precious internal memory).

[GSmith]

Be careful. I believe Menneisyys is really referring to read speed. And I respect his experience and thoroughness.

I have seen DRASTIC differences in *write* speed of different SD cards. I am not sure if there are as big differences in CF cards' write speed. CF I vs CF II refers only to size, not speed or age of specification.

Two good references for media speed are:

The CompactFlash Performance Database
http://www.robgalbraith.com/bins/multi_page.asp?cid=6007

Three Leading SD Cards Compared
http://gregkeene.typepad.com/h6315/2004/11/three_leading_s.html

[Kowalski]

Menneisyys refered that SD are faster than CF but my experiences show totally different results. i have both CF and SD cards from sandisk(both are standart, not ultra series) and CF speeds are remarkable faster than SD.

[maximus]

Thanks for the info, Menneisyys

My digital camera uses CF card, and I have on occasion put the camera's card in the PDA.

Then you have the right setup already, SD for wifi, CF for memory. Why change something that is already working fine ? Just get a bigger and faster CF. You can use it both on your PDA and camera.

[Mystery905]

I had a 128MB Sandisk that was EXTREMELY slow with writes.

I upgraded to a 256MB Lexar that was at least 8 times faster at writes than the Sandisk. (based on the number of cycles of the 'color' wheel writing various Excel spreadsheets)

Lexar for me from now on!

[Menneisyys]

Menneisyys refered that SD are faster than CF but my experiences show totally different results. i have both CF and SD cards from sandisk(both are standart, not ultra series) and CF speeds are remarkable faster than SD.

It all depends on the card in question. In plain throughput rates, SD's are generally a bit faster in recent PDA's. File creation time, which can even be in the second range with worse cards, is a completely different question - this is what makes some SD's so sluggish.

According to my benchmarks done on iPAQ 2210 / PL720, plain SD throughput speeds of plain SanDisk SD cards are higher than even better CF's, while file creation times are much worse. This is of extreme importance when, for example, in order to keep your main memory clean, you want to move your PIE cache to a storage medium.

I strongly recommend my latest PIE cache benchmarks at http://www.pocketpcthoughts.com/forums/viewtopic.php?t=36376 . They do show how a card (a SanDisk SD in this case) which has otherwise a larger throughput rate sucks in tasks when an app (PIE in this case) needs to create a lot of files on it.

The bottom line: getting a card that has slow file creation as opposed to "fast" card all depends on what you want to use it for. For example, if you only want to use your card for MP3 playback / recording / image wallet / static storage medium (ebooks etc) etc, file creation speed isn't that important (I use my SanDisk SD for these and have no complaints.). If you want to save a lot of files (e.g., Excel files -see the post above), or want to move your PIE cache to it, it can be of extreme importance, however.