How is the SD card used for performance by the OS?

**pizza_pablo** · 01-09-2013, 10:30 AM

While researching which SD card to buy, for the M, I found forums discussing faster performance using a class 10 vice a class 4 card.
Is this true?
How does the operating system use the SD card (as a swap file, extra ram, etc.)?

**rigdon420** · 01-09-2013, 10:58 AM

I'm not a genius but I'd have to say that the difference is the read/write speed which really probably wouldn't make a big difference. The sd card is external storage.

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**pdaniel219** · 01-09-2013, 12:25 PM

For what it's worth, I've read that class 4 cards with better with the new razr line. I've read in a few forums that the class 10 cards have issues. I can't say, because I'm using a class 4, and I've never had any problems, but I haven't tried a class 10.

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**pizza_pablo** · 01-09-2013, 02:26 PM

Thanks for the replies.
The posts, iI read, on another forum, suggested that phone performed faster, over all, not only when reading/writing to the SD card.

As far as running better with a class 4 vice a 10....I'll let you know. I am running a class 4 now and will be switching to a class 10.

**Pete7874** · 01-09-2013, 06:52 PM

Originally Posted by pizza_pablo

How does the operating system use the SD card (as a swap file, extra ram, etc.)?

Are you sure Razr M's operating system uses the SD card to actually function? That's the first time I hear of it, but I guess it's possible. However, I have never actually noticed any performance difference running with a card and without a card. Also, if certain part of the card was reserved for swaps or extra ram, you should be able to see this space subtracted from the available space on the card. Again, I've never seen it. I have also never seen any related system files present on the card. But it's possible that some rooted OS could take advantage of it somehow.

As for class 10 cards, I've used 3 different ones in Razr M. The only one that gave me problems was the infamous SanDisk Ultra UHS-1 32gb. Reading the reviews on Amazon, it looks like there may have been a bad batch of these cards released by SanDisk. For practical purposes, such as playing MP3s and watching videos, you won't see much performance difference between class 10 and class 4.

**pizza_pablo** · 01-09-2013, 09:32 PM

Thanks, Pete.
I didn't think about rooted phones.
I don't recall if that was the subject.
I was googling for class compatibility and saw a few comments about better performance.

**dki378** · 01-11-2013, 11:37 AM

I have used a Class10 with no issues. This is the one I purchased:

**magnes** · 01-12-2013, 12:30 PM

Does a 32GB card need to be formatted (presumably on a PC) before it is used on the phone? My Razr M arrives Monday, along with a SanDisk card, and I'd like to be fully prepared for the set-up.
Thanks.

**Pete7874** · 01-12-2013, 01:21 PM

Most cards are already formatted. If anything, you may want to format it using your phone before you start saving data to it.

**magnes** · 01-12-2013, 01:32 PM

Thanks so much. Will investigate how that's done. I already have the
.pdf User's Guide downloaded.

**Pete7874** · 01-12-2013, 01:58 PM

Actually, now that I'm looking at it, I can't find a Format option anymore in Jelly Bean. I know it was there in older Android OS versions. Settings... Storage... Erase Card is there, but I'm not sure if that also performs a quick format or not.

**magnes** · 01-12-2013, 02:31 PM

Don't sweat it. It wouldn't be fun without a little uncertainty/voodoo/romance. Verizon tech support can always talk me through it.

**revtech** · 01-18-2013, 10:06 AM

I guess I'd like to ask about sd cards for android phones in general. I've been thinking about a razr M but the 8 gb worries me; others have said 'no big deal it has an sd card slot', but then I've also heard that you can't put apps/etc on an sd card . . so is it only for music and movies and such, or what? Can someone maybe chime in on this or provide some use-case scenarios? Thanks

**Pete7874** · 01-18-2013, 10:22 AM

revtech, if you're using the factory OS, then yes, apps can only be put in the internal memory. Out of the 8 gb of internal memory, in practice only about 4-4.5 gb is available for storing apps and media. The rest is reserved for the operating system, I believe. Still, for most people that's plenty of space. I have about 50 apps installed, and that takes up about 0.6 gb. I know people love to install a lot of garbage on their phones, but how many of these apps do you actually use? I know that game apps tend to be larger, so if you like to play a lot of games, Razr M may not be for you. The "M" stands for "mini" after all.

SD card is used for media storage mainly (music, photos, videos, documents). If you root your phone, then you could also put apps on the SD card, if I'm not mistaken.

**revtech** · 01-18-2013, 10:45 AM

Thank you, I can do research but I always feel better hearing personal testimony. I don't play games so I suspected that 4-5 gb might be good enough but i wasn't sure.

**pdaniel219** · 01-18-2013, 11:20 AM

Same here. I was worried about the 8G, but it's not an issue at all. I have about 25 apps installed, about 10 of those are games, and I have plenty of space. Just get rid of apps you don't use. It's better for your phone anyway.

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