Hard drive for OS/applications?

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I'm going to treat my Mac Pro to a new hard drive for when Snow Leopard appears, it's going to be my OS/applications drive with my home directory on a different drive.

Capactity isn't that important, a 160Gb or so will suffice. Speed is what counts, I'm currently using a 320Gb F1 which I believe is single platter.

What's good to go for these days? A Velociraptor?
 
Not cheap, probably around £350. Normally with SSDs you'd get a smaller one though, put os,apps,maybe a couple of games on it, then HDD for other games/storage. It's the fastest though. £170ish for 80gb. You'll want to check mac compatibility perhaps though?
 
I'm in the same situation as you Feek. Currently using a WD Blue 640.

At the moment I am looking at getting an Intel G2 80 for my OS/App drive.
 
I have less than 30Gb of OS and Applications! An 80Gb would do the job.
 
are the SSD drives ok for os's with lots of small files and constant HD access? - i thought that this reduced the lifetime of these new SSD's?
 
If you're interested Feek, I have just updated the first post of the Intel X25-M G2 Solid State Drives thread with various bits of information. (Hopefully hailstorm doesn't mind :p but it was just to compile all the bits of information together) If you're looking at a fast operating system and application drive, then I would defiantly consider a Intel X25-M G2 solid state drive. It's just a shame these drives won't be available for around two weeks though.

Regarding the life expectancy of solid state drives, it really isn't as much of an issue as a lot people first think. Companies have said that if you were to write 20GB of data to the drive every day, then the drive will last for around 5 years.

Intel have gone several steps ahead of that and have guaranteed that you will be able to write 100GB of data to the drive for the next 5 years and your data will remain intact.

Anandtech said:
How Long Will Intel's SSDs Last?

SSD lifespans are usually quantified in the number of erase/program cycles a block can go through before it is unusable, as I mentioned earlier it's generally 10,000 cycles for MLC flash and 100,000 cycles for SLC. Neither of these numbers are particularly user friendly since only the SSD itself is aware of how many blocks it has programmed. Intel wanted to represent its SSD lifespan as a function of the amount of data written per day, so Intel met with a number of OEMs and collectively they came up with a target figure: 20GB per day. OEMs wanted assurances that a user could write 20GB of data per day to these drives and still have them last, guaranteed, for five years. Intel had no problems with that.

Intel went one step further and delivered 5x what the OEMs requested. Thus Intel will guarantee that you can write 100GB of data to one of its MLC SSDs every day, for the next five years, and your data will remain intact. The drives only ship with a 3 year warranty but I suspect that there'd be some recourse if you could prove that Intel's 100GB/day promise was false.

Intel X25-M SSD: Intel Delivers One of the World's Fastest Drives - How Long Will Intel's SSDs Last? (Page 4)


The Tech Report said:
So the X25-M shouldn't be short on performance, but what about longevity? MLC-based flash memory cells are limited to 10,000 write-erase cycles, giving solid-state drives a finite lifespan. When estimating the operating life of their drives, other SSD makers generally rely on a basic formula to calculate the number of cycles used:

Cycles = (Host writes) / (Drive capacity)

Intel says this formula oversimplifies the issue, and that two other factors must be considered. The first of these variables is write amplification, which refers to the amount of data actually written to a drive for a given write request. Intel gives an example in which a host system generates a 4KB write request that, thanks to a drive's 128KB erase block size, actually incurs a 128KB NAND write. Dividing the NAND write size by the request size yields the amplification factor, which is 32 in this case. Intel says the X25-M's write-amplification factor is extremely low at 1.1, while "traditional" SSDs have much higher amplification factor of 20.

The efficiency of wear-leveling algorithms also has a hand in determining an SSD's lifespan. If a drive is going to shuffle bits around to avoid bad cells and more efficiently use those available, it must do so without wasting precious write-erase cycles. Intel estimates the X25-M's wear-leveling efficiency factor at less than 1.1, claiming that traditional SSDs have an efficiency factor of 3.

Taking write-amplification and wear-leveling efficiency into account, Intel says the correct formula for cycling is as follows:

Cycles = (Host writes) * (Write amplification factor) * (Wear leveling factor) / (Drive capacity)

Using a write-amplification factor of 1.1 and a wear-leveling efficiency factor of 1.1, 20GB of write-erase per day for five years should consume only about 550 cycles on an 80GB X25-M. Using "traditional" SSD technology with an amplification factor of 20 and an efficiency factor of 3, the same write-erase load would use over 27,000 cycles. That's a huge difference, and to be fair, it's one that relies on values provided by Intel that aren't entirely consistent. Another Intel presentation from IDF estimates that "mediocre" SSDs have a write-amplification factor of 10 and a wear-leveling efficiency factor of 5, resulting in just under 23,000 cycles for our 20GB of write-erase per day example. That presentation also pegs the X25-M's efficiency factor at 1.04 rather than 1.1. We can't easily test a drive's lifespan ourselves, but we did ask Samsung for the write-amplification and wear-leveling efficiency factor values for its SSDs. Samsung hasn't responded yet, though.

If you don't want to crunch through the math, Intel estimates that the 80GB X25-M will last for five years with "much greater than" 100GB of write-erase per day. That's a relatively long time for much more data than most folks are likely to write or erase on a daily basis.

Intel's X25-M solid-state drive
 
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