CORSAIR S64/S128 SSD + M64 SSD + P256 SSD

[yefi]

Didn't see anything on this.

The S64/S128 (64GB/128GB) are MLC-based. They're rated for a conservative 90MB/s read and 70MB/s write, but use a Samsung controller, not the infamous JMicron, so don't suffer from the stutter issues. http://www.youtube.com/watch?v=qWiUW65DX7Y (N.B. the guy gets 150MB/s write because he hadn't formatted/filled the drive.)

The M64 is also MLC-based, but rated for 170MB/s read and 100MB/s write. edit: Uses a JMicron controller (Corsair say Revision B which doesn't stutter, we'll see....)

The P256, meanwhile, is clearly a direct competitor to the Vertex/Intel SSD: http://www.legitreviews.com/article/949/1/

[heiki]

The M64 is also MLC-based, but rated for 170MB/s read and 100MB/s write. Also uses Samsung controller.
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Unfortunately this is incorrect. It uses Jmicron controller. See here forum.corsair(dot)com/v3/showthread.php?t=78540 (cant post an url yet)

[yefi]

See here forum.corsair(dot)com/v3/showthread.php?t=78540 (cant post an url yet)

He says there that this an updated version of the JMicron, though I'm probably not alone in thinking it's a bad idea to let anything printed with JMicron inside an SSD.

[highlandsun]

The Corsair P256 seems like an excellent product at the moment.

http://forum.notebookreview.com/showthr ... ost4933442

[dhanson865]

See here forum.corsair(dot)com/v3/showthread.php?t=78540 (cant post an url yet)

He says there that this an updated version of the JMicron, though I'm probably not alone in thinking it's a bad idea to let anything printed with JMicron inside an SSD.

Doesn't matter if it is Jmicron or not. What matters is if the controller has enough cache. If the cache is measured in KB it is too small and you'll get stuttering. If the cache is measured in MB it is big enough and you won't.

JMicron JMF601 controller 4 KB cache? or is it 8KB?
JMicron JMF602A controller 8 KB cache.
JMicron JMF602B controller 16 KB cache.

You'll also see some drives using a JMB390 RAID with 2x JMF602B controller giving you effectively 32 KB cache.

Vertex SSDs use 32MB or 64MB on-drive cache.

Nicer SSDs use 128MB on-drive cache.

If you had an SSD with a jmicron controller and 32MB cache you wouldn't care that it was a jmicron.

Note the Corsair rep at http://forum.corsair.com/v3/showthread.php?t=78540 did say the Corsair 64GB SSD does NOT have on drive cache meaning it only has the 16 KB cache. Sure it has twice the cache of the jmf602a but that only reduces the issues it does not eliminate them.

Unless you have a hardware RAID controller with battery backup you need MBs of cache in your SSD. Anything less and you won't be happy.

[highlandsun]

The P256 is definitely a Samsung, and it's got impressively low power consumption as well as high performance.

re: cache size - kind of a moot point, there are no JMicrons with large cache. Therefore, if it's got a JMicron controller, it's best to avoid it.

[dhanson865]

The P256 is definitely a Samsung, and it's got impressively low power consumption as well as high performance.

re: cache size - kind of a moot point, there are no JMicrons with large cache. Therefore, if it's got a JMicron controller, it's best to avoid it.

Not true going forward. There are new Jmicron controllers that allow MB of cache.

JMF611
JMF612

The JMicron JMF612 SSD controller should be available to OEMs in late June or July and is different from Indilinx and Samsung because it can accept a wider variety of DDR or DDR2 cache, up to 256MB, rather than specifically "mobile DRAM" as well as, more importantly, a variety of NAND Flash IC from the likes of Toshiba, Intel, and Micron. This is instead of the most expensive Samsung chips which the Samsung and Indilinx controllers are currently limited to.

JMicron's current 602 controller costs $10 to 12, while the Indilinx is $15, there's no word on the price of the new 612 but we expect should be more competitive with Indilinx considering the savings that can be made elsewhere (in the cost of the cache memory)

I'm no advocate of Jmicron but I'm willing to keep a watch and see if they put out something worth buying.

Even if the Jmicron products aren't what I buy, the better they get the lower the price will be on non Jmicron products. Expect major price shifts when the 612 hits the market.

[fyleow]

There is more to the issue than just cache. Intel's X-25M doesn't use any DRAM cache for user data and yet it is one of the best performing MLC drives currently on the market.

The bottom line is that as of this point Jmicron hasn't been able to develop a controller without issues. I would be cautious about buying any SSD using a Jmicron controller regardless of how much cache it has.

[dhanson865]

There is more to the issue than just cache. Intel's X-25M doesn't use any DRAM cache for user data and yet it is one of the best performing MLC drives currently on the market.

The bottom line is that as of this point Jmicron hasn't been able to develop a controller without issues. I would be cautious about buying any SSD using a Jmicron controller regardless of how much cache it has.

Picking on the term "user data" is splitting hairs. The Intel SSDs have MB of cache and no matter how you slice it 16MB cache is better than 16KB of cache.

JMF602B = 16KB on controller and no on drive cache
X-25M = 256KB on controller and 16MB on drive cache

Somehow having 16 times the cache on the controller helps even if you ignore the 1024 times more cache that the dram chip provides.

The JMF602 is essentially a L1 cache only design where the X-25M is a L1 + L2 cache design.

I'm saying not having enough L1 cache or any L2 cache makes it something to stay away from. You are just saying the Jmicron name makes it something to stay away from. You might want to be a little more objective in the future.

[highlandsun]

If you believe JMicron, cache size wasn't their problem...

http://forum.notebookreview.com/showpos ... count=6226

I'm saying they've had a long track record of failure and refusal to admit their problems. Why should their future behavior be any different?

[reddyuday]

Well, things change fast in this product line!

The Corsair web site lists "performance series" drives, which are labeled by "P", and a newer "extreme series", which are labeled by "X". The extreme series have an "Indilinx Barefoot" controller. They have a smaller cache of 64MB but report higher speeds. They are selling for marginally higher prices than the performance series drives. The users on newegg have been generally happy with both the series.

[aztec]

I hope the 120Gb models drop to $200-250 range by Black Friday.