Plan For Memory?


lingenfr

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I have been looking at Class 6 32GB SDHC. The other thing I am considering is an SD Micro to SDHC adapter or similar. What are folks planning and where have you found good prices (other than eBay)? Thanks.
 
I just watch for sales here: CODE
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010070068%201053125651&name=Secure%20Digital%20High-Capacity%20%28SDHC%29


Got a class 6 16gb Patriot for $17 when it was on sale plus a mail in rebate
 
'lingenfr' said:
The other thing I am considering is an SD Micro to SDHC adapter or similar. What are folks planning and where have you found good prices (other than eBay)? Thanks.
Regarding where good prices are to be found, that depends on what country you're in. ;) Others have already suggested Newegg if you're US-based. If you're UK-based, or based in any of the other countries Play.com serves (full list here), then I'll recommend Play.com.

Purchasing flash-memory from eBay is too risky, as most such items sold there have their controllers reprogrammed to report false capacities, so I wouldn't bother with that myself. :p More info on that stuff here.

As for a microSDHC Card with an adapter to fit a full-size card slot, I would go for that if I had another device which could use the micro card, otherwise it would strike me as being a bit pointless. :p
 
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Class numbers don't say much except that anything below class 6 is probably trash; the classes refer to minimum transfer rates of 2, 4, and 6 MB/s, respectively.

Newegg is great, but also look out for OEM rebates and smaller sites like photo retailers; I got three 8 GB Sandisk extreme-IIIs (the older 20 MB/s r/w ones, but still cool) for $20 from Abe's of Maine after a $70 rebate from Sandisk. My prepaid Visa card arrived yesterday.
 
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'typs lik dis' said:
Class numbers don't say much except that anything below class 6 is probably trash; the classes refer to minimum transfer rates of 2, 4, and 6 MB/s, respectively.
Why would anything less than 6MB/s be bad? I really can't think of anything you would need 6MB/s for.
 
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'arrrgh' said:
'typs lik dis' said:
Class numbers don't say much except that anything below class 6 is probably trash; the classes refer to minimum transfer rates of 2, 4, and 6 MB/s, respectively.
Why would anything less than 6MB/s be bad? I really can't think of anything you would need 6MB/s for.


Moving lots of data back and forth?
You have a point, you can stream video and load game data comfortably at 6 MB / second, but a faster write speed would make the transfer of videos to the Pandora much better.
 
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'arrrgh' said:
'typs lik dis' said:
Class numbers don't say much except that anything below class 6 is probably trash; the classes refer to minimum transfer rates of 2, 4, and 6 MB/s, respectively.
Why would anything less than 6MB/s be bad? I really can't think of anything you would need 6MB/s for.

Copying things (like MP3s or movies) to the card the very first time you want to use it.
If you've got direct DVD rips, you might push the bounds of playback speed, even with a class 6, but otherwise yes, you're right.
 
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A 6 MB / s card needs 166.6 seconds to read 1GB of data into memory, plus the amount of time needed to re-allocate this memory, since the Pandora isn't going to have a gig of free memory ever.

The Pandora's memoyr is 256MB, so a card that averages a minimum 6 MB/s read and write can load or store the entire contents of RAM in about 42 seconds.

Which isn't very good news for hibernation, but most devices don't hibernate very quickly anyway, and the Pandora's suspend-to-RAM uses so little power that hibernation should be unnecessary.

edit: According to the Wikipedia, DVD quality MPEG2 video is around 5 Mbits per second. If you account for some overhead, this is still only 1/8 th of a 6MB card's read speed.

DVD playback from SD shouldn't be any problem.
 
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'WizardStan' said:
'arrrgh' said:
'typs lik dis' said:
Class numbers don't say much except that anything below class 6 is probably trash; the classes refer to minimum transfer rates of 2, 4, and 6 MB/s, respectively.
Why would anything less than 6MB/s be bad? I really can't think of anything you would need 6MB/s for.

Copying things (like MP3s or movies) to the card the very first time you want to use it.
If you've got direct DVD rips, you might push the bounds of playback speed, even with a class 6, but otherwise yes, you're right.

I didn't mean that a Class 6 isn't a good thing, but the way typs lik dis said it it seemed that everything other than a Class 6 was crap. Anyway, if you have 3GB of data to move, on a Class 6 it'll take 8 minutes and on a Class 4, it'll take 13. Not a huge difference, really.
 
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'arrrgh' said:
I didn't mean that a Class 6 isn't a good thing, but the way typs lik dis said it it seemed that everything other than a Class 6 was crap. Anyway, if you have 3GB of data to move, on a Class 6 it'll take 8 minutes and on a Class 4, it'll take 13. Not a huge difference, really.
If you've got 32GB to move, things look very different. With the fastest cards, about 17MB/s from the benchmarks I've seen, you're looking at 30 minutes. On a slow class 4 card, that would take more than 2 hours. 90 minutes is hardly inconsequential.
 
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'sdedalus' said:
'arrrgh' said:
I didn't mean that a Class 6 isn't a good thing, but the way typs lik dis said it it seemed that everything other than a Class 6 was crap. Anyway, if you have 3GB of data to move, on a Class 6 it'll take 8 minutes and on a Class 4, it'll take 13. Not a huge difference, really.
If you've got 32GB to move, things look very different. With the fastest cards, about 17MB/s from the benchmarks I've seen, you're looking at 30 minutes. On a slow class 4 card, that would take more than 2 hours. 90 minutes is hardly inconsequential.

I was calculating using the minimum 4 and 6MB/s ratings. You are comparing a high quality card that can go up to 17MB/s, to the base Class 4 standard of 4MB/s which isn't really fair as there are Class 4's that go faster than 4MB/s too.
 
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'lulzfish' said:
'arrrgh' said:
there are Class 4's that go faster than 4MB/s too.
?
So is the class just the write speed minimum, and the read might go above that?

The class is the guaranteed speed, so if you bought a Class 6, it would be sure to have at least 6MB/s read and write, but there's nothing stopping it from being faster, but how fast it actually is depends on the card itself.
 
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Yeah, I knew that, but I had a cache miss and...

'lingenfr' said:
I have been looking at Class 6 32GB SDHC. The other thing I am considering is an SD Micro to SDHC adapter or similar. What are folks planning and where have you found good prices (other than eBay)? Thanks.
To answer the original question, I have a 1GB card and a 2GB card from my digital camera. I'm probably putting the 2GB in the Pandora since it will be holding movies and the like, and my camera doesn't get enough use to need the 1GB.

I suppose I'll buy some more from Newegg eventually, but most of my data will be streamed from my laptop, so the SD cards are just for watching videos on road trips or for small programming projects.

I've always wanted to buy a flash device and have a shell script dump random data onto it until it dies, just to see how long they really last, but I've never bothered... Perhaps one day I'll give that a shot as well, since I won't need my older cards for anything.
 
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Wow, it is like a sociology experiment putting a simple post on here :lol: Thanks, I have done a *little* business with newegg and have bought quite a few memory cards from eBay as well with no problems. I was thinking of the microSD to SDHC adapter as a way to get larger memory sizes and a cheaper upgrade path. Maybe it is a bad idea.
 
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I have an A-Data 16GB SDHC card that I got to put in my Cowon D2. I may pick up a fast 16 or 32GB SDHC card in addition to that.

Incidentally, I agree with the sentiment that the biggest benefit of a fast SDHC card is writing / transferring large amounts of data to it (like media files, etc.). Having a super-fast flash memory card did make a noticeable difference in data access and program loading speeds for me when using a Dell Pocket PC years ago (it was a SanDisk Extreme II I think). But that may have been somewhat subjective.
 
'typs lik dis' said:
Class numbers don't say much except that anything below class 6 is probably trash; the classes refer to minimum transfer rates of 2, 4, and 6 MB/s, respectively.
not true. read a recent SDHC card shootout and the winner was a class 4 card. (the average read/write speed of a good card is around or above 20/15 regardless of class.)
 
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Class is minimum write speed when the card is empty. If you got a bunch of fragmented stuff on it then speeds can drop below that. There are cards that can write over 20 MB/s, just look for the ones marked 150x (max rating). 6MB/s = 40x.

Again, larger cards tends to have lower speeds then smaller cards. If you really want a fast card you should look for benchmarks.
 
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