Is a class 10 micro SD as fast as WP's internal memory?

[WasteSomeTime]

Like the title says. Is it as fast? Or getting a class 4 give the same results?

 

[azcruz]

Class 10 = 10MB/s, so no.

UHS I = 50MB - 100MB
UHS II = 310MB

The Surface does not use UHS bus AFAIK.

 

[N_LaRUE]

Class 10 = 10MB/s, so no.

UHS I = 50MB - 100MB
UHS II = 310MB

The Surface does not use UHS bus AFAIK.

Were they asking about Surface or WP or just in general?

 

[WasteSomeTime]

I guess I should have just said windows phone.

 

[azcruz]

I use Class 6 on all my devices, Xperia V, HTC 8S, Surface RT, and it is enough for *my* needs.

 

[WasteSomeTime]

But is it as fast the time it takes to access flash memory files?

 

[azcruz]

I believe I answered that question already.

 

[Neusyn]

From what I've seen it really depends on the device and card. Quite a few devices will not see much or any improvement above class 6. Afaik Nokia Lumia also are no exception so I'd say save money and get a class 6.

 

[WasteSomeTime]

I believe I answered that question already.

You did . . . Solely based on * your * needs, not mine. I want the to squeeze out all the performance I can to make it feel the same as accessing flash memory.

 

[xandros9]

in general use, it shouldn't matter much. now if you were doing some heavy lifting on a timetable like running big programs of the card (in Surface for example), or needing to rapidly move and work with media ASAP, go for it.

 

[RustyU]

Simply put: No.

EMMC beats the crap out of SD.

 

[azcruz]

You did . . . Solely based on * your * needs, not mine. I want the to squeeze out all the performance I can to make it feel the same as accessing flash memory.

Sorry if I was vague, I was referring to my reply of

Class 10 = 10MB/s, so no.

As an example, my mid-range HTC8S using the MSM8227 SOC use dual-channel LPDDR2-800 at 12.6GB/s

 

[Moiz Mian]

I can't believe this hasn't been answered yet. I don't have a micro usb cable on me, but connect your phone to your laptop and try dragging and dropping a file from your laptop to your device and back, and then report your speed of both here. That will give you read/write times.

I personally think that the speed of a high speed class 10 will be similar. I have a 32GB 30MB/s microSD card that I bought from amazon for like $25.The internal memory should also be about 30MB/s

 

[Moiz Mian]

Ok, I just ran a read/write test. If anyone else wants to confirm, I'm getting 12.5MB/s write and 18MB/s read. That's about equal to class 10. Remember class 10 means MINIMUM of 10MB/s.

Amazon.com: SanDisk Ultra 32 GB MicroSDHC C10/UHS1 Memory Card with Adapter (SDSDQU-032G-AFFP-A): Electronics

This is what I have, and it is faster than the internal memory. 30MB/s

 

[Moiz Mian]

Simply put: No.

EMMC beats the crap out of SD.

No, while EMMC might be faster, it's bottlenecked by the transfer mechanism, which is usually crap on cellphones and tablets.

 

[anony_mouse]

Sorry if I was vague, I was referring to my reply of As an example, my mid-range HTC8S using the MSM8227 SOC use dual-channel LPDDR2-800 at 12.6GB/s

Just to note that is the speed the bus operates, not necessarily the speed of the memory. It's a theoretical maximum.
Also DDR is used for connecting dynamic memory (i.e. RAM), not flash, so isn't relevant here.

 

[Guzzler3]

I can't find the web page anymore, but I do remember that WP devices are supposed to use UHS compliant microSD cards (if a microSD slot is used) to be "certified' by Microsoft as a compliant device to run the WP operating system.

Now the fun part. You can have a microSD card that is Class 6, but is also UHS 1. Meaning that if you put it in a device that is using the old bus technology (aka Class) you will get a transfer rate of a minimum of 6 Mb/s. But put the same card in a device that uses the newer bus technology (aka UHS) you will get a transfer rate of at least 10 Mb/s.

Even more fun. Class and UHS speeds are spec'd as minimum speeds to be certified. So a UHS 1 class card with always get you at least 10 Mb/s. But it could be faster, depending on the manufacturer and how well they make the card, up to 30 Mb/s. Then the card is certified as a UHS 3 card.

Same goes for Class ratings. As soon as the cards transfer rate increases enough to the next level (2 -> 4 -> 6 -> 10).

So...what you should take out of this, is to stop shopping via the "Class" rating and look at the "UHS" rating for microSD cards for Windows Phone.

 

[Guzzler3]

Another thing about testing card speeds via a PC. Don't. For some reason most PC makers don't put the SD card reader on a fast bus inside the PC (minimize costs possibly). Tom's Hardware researched this awhile back and came up frustrated at the transfer rates. The all maxed out a set rate, even if the card was rated at a higher speed.

It's only device manufacturers (phones, cameras, etc.) that spend the extra money to put the SD reader on fast buses.