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SD card used for an SSD
- Thread starter zarathu
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Even the fastest SD card will be slower than a conventional HDD, thus you will not have any SSD-like experience.
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The advantage of a bootable SD card is portability. You can carry your OS, Apps and documents in your pocket.
The disadvantage, as has already been stated, would be speed. The SD card will be nothing like an SSD Speed wise and will be will slower than a XXXX ( pick a speed, it doesn't matter) RPM HDD.
zarathu said:
The advantage of a bootable SD card is portability. You can carry your OS, Apps and documents in your pocket.
The disadvantage, as has already been stated, would be speed. The SD card will be nothing like an SSD Speed wise and will be will slower than a XXXX ( pick a speed, it doesn't matter) RPM HDD.
Yes. SD cards are not designed to have the performance levels of a dedicated SSD.
Even if they somehow could, the card reader is a USB 2.0 device (400Mbit/sec max.) while a dedicated SSD is going to be running off the SATA 2 interface (3Gbps/sec).
Completely agree. Top range class 10 64Gb even some 32GB SD card from major manufactures cost the same or more the cheapest 64GB ssd. So why would you pay more and settle for USB performance? Just buy a cheap 64GB ssd and run it via Firewire.
And you're back to square one again. Theres's no point in getting an SSD when you're going to run it through Firewire since it doesn't have the bandwidth to take advantage of the SSD. If you're going to go firewire, you're better off getting a 7200RPM HDD which will not only be far far more cheaper, but will also have vastly more space.
Only connect SSD with Thunderbolt.
Where can you purchase a dedicated Thunderbolt reader? The point here is not to use it for your entire HD, but for some selected things such as storing photos in Aperture that you need very quick access to.
Still slower than a 5400RPM HDD, except with access times.
Still hypothetical, thus non existent.
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A traditional hard drive's can sustain ~80 - 100MB/s.
Also not sure what the lifespan of the SD card would be like if there are a lot of writes tot he card. Flash memory has a finite number of reads/writes.
Actually:
http://www.google.com/products/cata...Tr73E5LKiAKBzam2Dg&ved=0CDUQ8wIwAQ#ps-sellers
at 90MB/s, beats out most HDD....but comes very short compared to SSD.
http://www.google.com/products/cata...Tr73E5LKiAKBzam2Dg&ved=0CDUQ8wIwAQ#ps-sellers
at 90MB/s, beats out most HDD....but comes very short compared to SSD.
Although FW does not fully exploit the speed potential of a SSD, there are many forum posts here from users who put a SSD in an external FW 800 enclosure and see much better speed and system responsiveness than with an internal HDD. SSD in FW 800 external is a very viable alternative.
The card is only rated for 45MB/s... 90MB/s is marketing speaking. Also, UHS cards may require a UHS enabled card reader to take advantage of the speed.
I'm sure there are speed improvements that would warrant it as a viable alternative, but I think it's value is greatly diminished by bottlenecking the SSD through a slower interface. The speed increases are probably slight and I don't think it's worth splurging the money over.
I think that concentrating solely on the bandwidth available is a mistake. This is only one factor in the overall performance of a disk drive. The seek time (i.e. the time it takes to find the data you need) can be just as important if not more so. For example booting a computer involves accessing lots of small files that maybe scattered across your drive. In this situation seek time will be a major factor in how long the whole process takes.
Seek time is one area were SSDs are vastly better than HDDs, which isn't surprising when you consider that a HDD has to physical move heads around to access your data. It is also one area where the limited bandwidth of Firewire is not going to be a problem.
If anyone is interested this wikipedia article goes into the complexities of comparing SSDs and HDDs.
Memory cards, even fast ones, are not optimized for high IO loads and thus will be very slow. Their controllers are only optimized for low power consumption and linear reads/writes. For SSD controllers, it's quite the opposite.
Not entirely correct. It is limiting, but the main reason why SSDs feel so much faster is not the linear read speed. It's the low access time that makes them fast. When reading non-sequential data, HDD speeds quickly drop to a fraction of their theoretical maximum because of the access times.
