How Important Is Read Speed For Sd Card?


Probably very important. Because I know that problems with video and audio syncing during video playback has been put down to the GP2X not being able to read the data fast enough.

Personally, I'm unsure, though. I think that the sync problem is more to do with the way that the video's encoded.
 

I asked the same question, huh? Just kidding. I checked into the various speeds of a few SD cards and ATP seems to be good. Beating out Sandisk, Lexmark, etc. Though, I haven't checked every brand it's just the easiest for me to get. Hopefully someone on this forum with a GP2X will give us some impressions. MY concern is that movie's will lag, or audio won't be in sync!?
 
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I'm not sure the sync problems are down to the card's speed, more the implementation of the video codecs... I'm using an ancient 128MB card, and have no sync problems with DivX encoded movies at all, just XviD.
 
Right now the SD driver isn't even capable of reading that fast, which of course could change later on. But unless that isn't changed, a highspeed SD card is completly unnecessary.
 
Pretty much every SD card on the market has bandwidth well above the bitrates the videos are encoded as. The XviD problems will be fixed with future firmware updates. Patience.
 
I have a few different SD cards of various speeds & sizes.

On all of them Divx files that the gp2x is able to read play fine while Xvids don't.

Also, The problem with Xvids always seems to be that it plays the video at double speed and the audio at regular speed. I don't see how that could be caused by card speed.
 
Got me a 2GB 150x SD card and a (very) cheap 256mb 66x SD card for flashing the GP2x so I can use my 2gb card :p

edit:
oh, and when it comes to actual "speed" 150x seems to mean 15mb/s write speed (snice that's what it says on the back of the package) and 22,5mb/s read speed.
I've seen this on a website too. Can't seem to find it now though :/
 
MMC is not neccessarily slower.

I have an A-Data "MMC 4.0" 1GB 60x card and it works very fast. I am able to watch the 720x500 whatever mp4s right off of it just fine. and it only takes a couple seconds to move 50 or so megabytes onto it.

the carton says 15MB/s read, 8MB/s write. sounds fine by me, I have never seen a move encoded above 2MB/s anyway.


Edit: I don't have my GP2X just yet, so that is reading off of my crap generic usb 2.0 12-in-1 adapter.

Edit 2: I just read my card and the sticker says 100x I guess I must have bought the one for a couple dollars more.
 
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