aximfanatic

Hi, I wanted to know if anyone has both and SD and a CF card....I was using activesync to transfer files and when I tranfer from my pc to CF card...its not bad..but when I tranfer from PC to SD card....its really slow..


Does anyone else notice this...or coulod it be my SD Card?

I have the Kinsgton 128(the one from eCost) and I have a 256 Lexar CF card..

Thanks for any help in this...i am thinking of trying another SD if i get a chance....

cmms_axim

I have a Simpletech 256 and it works great for me. I would give simpletech or anything panasonic a shot if your looking for speed.


Hope that helps bro


CMMS

aarcam

I believe speed issue is a function of two things brand of card and type of card (SD, CF...)[not getting into speed ratings on some of the cards here]
I think CF is generally faster than SD (and cheaper), however, my 256 Sandisk CF is noticeably slower than my 256 Lexar SD (copying files on the device and transferring via active-suck)
For further comparison, my Lexar SD was faster copying files than a friend’s 256 Sandisk SD card.
From your specific instance it looks like the CF is faster than SD (typical) and may be compounded by the brand of the card. I have no experience with Kinsgton media so I cant say much about brands here, but the general consensus is the Lexar is near the top.
This is a pretty gross generalization, so YMMV.

pswets

Lexar is, in my experience, great, both for CF and SD. Kingston is also good (I've gotten one fairly recently.). I'd avoid this particular problem. though, by springing for a card reader to plug into my pc. I was just yesterday at office max (or office depot, dunno the difference unless I'm looking at the logo) and they had card readers for $8 ot $10, but free after mailin rebate. Card readers can certainly be had anytime for under $20, and it is not much work or time to find one for under $12.

Not really an answer to your question (I don't know the answer!), but an oblique way to sidestep it.

JeffLewis

My understanding is that CF is parallel (it's essentially the same as PCMCIA which is similar to ATA) while SD is serial or mostly serial. I say this because I'm sure I've read somewhere that SD uses four bits at a time.

Either way, the big difference is that CF can move data in wide blocks at a time, while SD has to squirt the data and control info a bit at a time.

At low speeds, parallel wins over serial, but as we're seeing with USB2 and Firewire, with the right signal conditioning, at high speeds, serial can be faster than parallel.

At the moment, SD isn't fast enough to beat CF and in my experience, all SD cards I've tried are significantly slower than equivalent sized CFs, but as someone's noticed, we're seeing faster and faster cards. CF is up to 48x now - or around 5Mbps.

Another issue is that CF's standard is openly available while SD's is proprietary. (Weirdly - CF is essentially the same as PCMCIA, which is proprietary... go fig...) That means it's more likely that CF memory and devices will be compliant to standards.

We've already seen many problems with SD cards (see HappyCheeseCake's website on these problems - you can find references on Aximsite). Ironically, the worst offender seems to be SanDisk - the company that actually defined the SD standard. Then again, they also screw up CF cards. I recently purchased a SanDisk 256MB CF card and it was essentially unusable - the only one I've ever seen with this problem.

Another big problem with SD - or rather with SDIO - is that it's very hard to put any kind of serious device in one. SD's main advantage, that they're small, makes it hard to put something like a modem or GPS in it simply for mechanical reasons.

Fortunately, the PCMCIA group are in the middle of ratifying a new standard for PCMCIA cards based on a hybrid of PCI-X and USB2 protocols to create a sort of 'super-CF' card with a USB2 or PCI-X interface. This provides all the advantages of a simple connection (which is SD's main advantage), but with a larger range of package sizes and a widely used, simpler and standard interface.