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Surface RT and Surface Pro sdxc slot



how fast can Surface RT and Surface Pro read / write to an SDXC 10 class card?

I want to buy a SDXC card (for my Surface RT and for my hopefully soon owning Surface Pro) but i'm not sure if i will limit myself with buying a to slow SDXC card.

Right now i'm considering the following card.

SanDisk SDSDXPA-064G-X46 Extreme Pro SDXC 64GB


The card is expensive without knowing if i will have an Advantage by using such a fast card.

Which card do you have for your Surface RT and Surface Pro?


Sent from my Windows 8 device using Board Express Pro
My experience on my RT is around 20MB/sec. That is from the SDXC to local storage. This is SanDisk.

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I'm running a PNY 32GB Hi-Speed MicroSDHC Class 10 for Tablet PCs. No idea what speed it runs at. I paid $17 at Staples for it.
I'm using a SanDisk 64GB Ultra that cost me about $60US. I haven't measured the speed but I can tell you I don't get any lags with music or videos, and documents open up promptly (although they would open faster if stored locally).
thx so far for the replies.

Can someone with a surface pro share his experience with us?

Can someone with a surface pro share his experience with us?

Joga --

Wow, it's been a long, long time since I did a Time & Motion Study, but I do still have my mechanical stopwatch. I didn't use it for this, though; I used a desktop stopwatch. It's raining this morning, so can't take the dogs out back -- well, I could. They would go, but I won't. So, time for a little experiment.

I didn't have a really big file on the Pro, but did have a 1.2G video file, so I made three copies of it, put them in a folder and moved it back and forth.

Surface Pro 128GB
C = Surface Pro SSD
D = SanDisk 64GB Mobile Ultra MicroSDXC Class 10 Memory Card
Folder contained 3 copies of a 1,259,303KB file, or 3,777,909KB
Transfer Speed was observed from the Details section of the file transfer block. The speed fluctuates during the transfer. "Range" is inexact.
Elapsed time was measured by the desktop stopwatch.

I transferred the folder from D to C; then transferred it back from C to D into an empty folder.

Observed results (non-scientific):

D to C = Range 38-39, Typical 38.7 -- Time 1:33
C to D = Range 11.0 to 14.8, Typical 12 to 13 -- Time 4:48

You can do the math.

That acrid smell is from some olde SIMMs & DIMMs (with a little bit of core memory for nostalgia's sake) being activated after a long period of idleness.

Hope this tells you what you want to know. It's still raining, so I'll be here if you want something else.

Take care,
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great, thx for the effort and all the infos.

I think i will take a cheaper sdxc card and just store my user data on it.

Maybe i should also go with the Surface Pro 128 GB when it's released in Germany.

Do you have a slower card that you could test? Just wondering if there is a difference.