Sdxc Support?


Kramy said:
Chip said:
This is very much true. I have many discs from 4-6 years ago that are no longer readable. With 1TB drives dropping below the $100 mark, hard disks are the cheapest and most reliable form of long term storage.
Yep. I made the flip to HDD-based backups a year and a half ago. It's definitely the cheapest way to go, and the longest lasting.

Unless you get a crummy Seagate like I did. :lol:


The problem with archiving to hard drive is that I've heard that the internal viscosity and such can break down if stored for long idle periods, the oils and other things inside are designed for constant use.
 
Last edited by a moderator:
cbox said:
The problem with archiving to hard drive is that I've heard that the internal viscosity and such can break down if stored for long idle periods, the oils and other things inside are designed for constant use.
Tell that to my 40GB HD's i still have around. And yes, they still work perfectly :)

I have seen dead hd's on my old job, 7 years old, broken. Send to data recovery, and bingo, all your data 100% back... In reality, the physical / magnetic data on the plates is more time proof, then cd/dvd's imho.

Chip is right when it comes down to dvd's. There is a degradation of the quality ( even if they are stored in optimal condition ), down to the point that they are unreadable. The problem is the material used in the layers to write to.

Take a look a pressed cd/dvd's. Those things last way longer then any off the cd/dvd's you can burn. Also, going cheap is a bad thing, when it comes down to cd/dvd's. They are not only more error pron when first used, but will not last as long. I have seen a lot off mixed results from cd/dvd's ( to be honest, more so on dvd's, especially the cheap stuff from when dvd writers first got affordable ).

The trick with HD's is easy. Buy a few HD's. Wait for the prices to drop. Buy some more with more space, sell your old ones. Repeat. In the end, you can keep moving your data from hd generation to generation. Aka, go from 250's to 320's, to 500's, to 750's.

The advantage is:
- Your data gets rewritten
- You constantly upgrade your space
- You can sell your old hd's ( and get a nice price still as they are not that old )
- Point above, and buy new hd's with only a small amount off money needed ( as you recover 60 to 75% off the cost from the old hd sales ).

Cd/dvd's? Well, forget about any second hand market, as you can only write one's. And nobody is going to pay a fair price for rewritable cd/dvd's.
 
Last edited by a moderator:
Ravnos said:
Bryce Leo said:
Svartalf said:
Heh... I can envision many people getting some pretty hi-definition pr0n at that point... ;)
I think you need to really consider how much resolution you want. I'd much rather watch 320x240 pr0n than count hairs on a cooter....


If you watched pr0n at a higher res, you'd probably notice that most porn girls shave. ;)

Yeah, and at HD resolutions you could also estimate how often they do it... :ph34r:
 
Last edited by a moderator:
Benjiro said:
Chip is right when it comes down to dvd's. There is a degradation of the quality ( even if they are stored in optimal condition ), down to the point that they are unreadable. The problem is the material used in the layers to write to.

Take a look a pressed cd/dvd's. Those things last way longer then any off the cd/dvd's you can burn. Also, going cheap is a bad thing, when it comes down to cd/dvd's. They are not only more error pron when first used, but will not last as long. I have seen a lot off mixed results from cd/dvd's ( to be honest, more so on dvd's, especially the cheap stuff from when dvd writers first got affordable ).
I looked into this a bit when getting old 8mm converted. As you say, the problem of degradation of DVDs is often exposure to air of the layer being written to. However, you can get DVDs with gold layers, which are supposed to be archival quality for many, many years.

I haven't seen anything about the lasting quality of the plastic layers which surround the written layer though. The 8mm films I have lasted 60 years. I can only hope the gold DVDs can last as long.

I've never seen anything about backing up to SDHC. Now that the SDXC format is promising an upper bound of 2 TB, I think people would try it. I wonder what it's shelf-life is/will be, in that regard.
 
Last edited by a moderator:
I think it needs to be mentioned again that SDHC also had an upper limit of 2TB, and the speed was limited by the manufacturing process, not by the spec.

SDXC looks more and more to be another licensing gimmick. There is nothing new about the technology that will automatically enable higher capacities and speeds - only the specification has changed. Unless they have come up with a new manufacturing process, SDXC cards are going to be the same capacity and speed as SDHC cards at launch.
 
Chip said:
I think it needs to be mentioned again that SDHC also had an upper limit of 2TB, and the speed was limited by the manufacturing process, not by the spec.

You need a license to product SD cards, and you need a license to use the technology (which includes using the SD logo, name, etc). That license states you must abide by the specification, which says:

This version of specification limits capacity up to and including 32GB
Speed: Default mode: Variable clock rate 0 - 25 MHz, up to 12.5 MB/sec interface speed (using 4 parallel data lines)
High-Speed mode: Variable clock rate 0 - 50 MHz, up to 25 MB/sec interface speed (using 4 parallel data lines)

So you can say that the speed AND size IS limited by the specification.

The SDXC specification allows upto 2TB and 104MB/sec. However, it doesn't yet state how those are specified unless you pay several thousand dollars to the SD Org. We are assuming that they are just using some of the reserved bits in the CSIZE field and increasing the clock rate, but that may not be the case (after all, 200Mhz across 4 parallel data lines is faster than a lot of ram modules, and so may require hardware modification to ensure all traces are of the same length).

So,
Standard Capacity SD Memory Card: Up to and including 2 GB
High Capacity SD Memory Card: More than 2GB, Upto 32GB
Extended Capacity SD Memory Card: More than 32GB, Upto 2TB
 
Last edited by a moderator:
aq21 said:
There are SD (not SDHC) 4GB cards.

Which are hacks, do not conform to the specification, and as such, do not work on all devices.
 
Last edited by a moderator:
Squidge said:
So,
Standard Capacity SD Memory Card: Up to and including 2 GB
High Capacity SD Memory Card: More than 2GB, Upto 32GB
Extended Capacity SD Memory Card: More than 32GB, Upto 2TB
If it is as simple as this, why was all the fuss made about the exFAT file system? FAT32 (which is the most common file format used for SDHC cards, according to Wikipedia) allows partitions of 2TB, even if the max file size is 4GB. Whilst exFAT does offer improvements over FAT32, why even mention it when launching the new SD card format? Maybe I'm reading too much into this...
 
Last edited by a moderator:
Its just the recommended file system by SDCard org. Most likely due to the file size issues.

You can of course reformat the cards as FAT32 like you can at the moment with Linux and ext2/3.

However, every device which states that it supports SDXC must support ExFAT if thats what the spec defines.
 
Squidge said:
However, every device which states that it supports SDXC must support ExFAT if thats what the spec defines.
That makes sense. SDXC cards, bring 'em on! Looking forward to improved SD card capacities (especially if it means reduced prices for current SD card sizes).
 
Last edited by a moderator:
Squidge said:
aq21 said:
There are SD (not SDHC) 4GB cards.

Which are hacks, do not conform to the specification, and as such, do not work on all devices.

And are much more expensive than SDHC 4 GB cards.
That being said, they do work in places that an SDHC 4GB card would not. For instance the SD700IS digital camera I have.
 
Last edited by a moderator:
I have two 4gb SD cards that I got before the SDHC specification was created and have been able to use them in every device I've tried.
 
I have an SD700 IS aswell.. interesting.

The price drop in SD and SDHC cards will be amazing I think. I can't wait. I do still hope that the Pandora can use SDXC.
 
Back
Top