Sd Card Speed


Dead1nside

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Hello, I was just wandering since 32GB cards are really still quite expensive (at least compared to the 16GB in the UK) I was thinking about getting a 16GB SDHC card, which most seem to be Class 6, whereas the 32GB ones are Class 2 - will this speed difference have any noticeable, detrimental effect to the operation of the Pandora?

Thanks.
 
The class of the card determines the minimum write speed. Class 6 means at least 6MB/s. Class 2 is at least 2MB/s.

Getting a higher class card means a higher minimum write speed, but it won't necessarily be faster on average.

NOTE: There is no guarantee that a card actually matches the listed class. The manufacturer decides the class, and it isn't officially evaluated by anyone.
 
Stuff will load slower, but the Pandora's OS is stored on internal NAND, so it won't be detrimental, just slower.
Not slower as in "frames per second", but applications on that SD card will take longer to start and it will take longer to load files from it.

You should probably look up benchmarks, though, the Classes aren't very meaningful.
 
Mmm, that is indeed what I thought. Considering the OS is on the internal NAND though, as you say it'll just be throughput that's effected. I'll take a look at some of those benchmarks.

Thanks.
 
A movie will have no problem playing in real time off even a class 2 card. SNES roms will take up to 1 second to load. N64 ROMS will take about 8 to 12 seconds to load vs 2 to 4 from a Class 6. These are the estimated maximum times, read speed may actually see no difference and be blazingly fast.
So as far as playing stuff off the card, I wouldn't worry about it at all.
The biggest hit comes from writing stuff to the card. In order to fill a 16 gig class 2 card, it could take up to 8 hours. A class 6 could take up to 2.7 hours. These are theoretical maximums, reality usually sees them much closer in speed than you expect.
 
Actually, the SD card ratings specify their *minimum sustained* write speed.The class doesn't say anything about read performance.

My class 2 16 gb card (i think its a Kingston) reads at 22 mb/s, my class 6 16 gb cards (Transcend) read at 17 mb/s.
 
drkIIRaziel said:
Actually, the SD card ratings specify their *minimum sustained* write speed.The class doesn't say anything about read performance.

My class 2 16 gb card (i think its a Kingston) reads at 22 mb/s, my class 6 16 gb cards (Transcend) read at 17 mb/s.

Very interesting to note. The real world differences.
 
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drkIIRaziel said:
Actually, the SD card ratings specify their *minimum sustained* write speed.The class doesn't say anything about read performance.
If the read speed is less than the write speed, there is a sever problem somewhere.
 
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i will wait until the pandora is released i have a crap 512mb sd card hanging about for testing but i would like to see improvements in the classification of cards to level out before investing more money in them...
would love to buy two 32 gb cards but 2x16 will surfice :)
 
I have meager memory demands, so I've been picking up cards at bargain prices. I have a 16gb and 2 4gb. all 3 are rated at class 6 but the 16 is just a joke by comparison. But if it will hold my roms and PSX images I'll be more than satisfied :)
 
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