Life just isn’t fair. When I met with Crucial at CES to talk about its first foray into the high performance SSD market I was given very high expectations for reliability and the testing that Crucial would put the drive through. We talked about the failure of other controller vendors to do adequate testing. Even Intel’s own follies. Crucial assured me that validation testing was high on the priority list.

The company already tests hundreds if not thousands of configurations for its memory. Slotting SSDs into the mix wouldn’t be difficult. In contrast, most of the vendors who ship Indilinx and SandForce drives don’t have nearly the validation experience or infrastructure in place to gain it.

Then, just weeks after I got my C300, the drive stopped working. Crucial sent me another drive which didn’t die, but let me discover that the C300 had serious issues when it came to worst case scenario performance. Similar to the original X25-M firmware when given a random enough workload, the RealSSD C300 could be backed into a corner that it would never get out of.

I dropped the C300 from my list of even potential recommendations while Crucial worked on a fix. Meanwhile SandForce’s partners had been shipping drives, with relatively few problems. To make matters worse? The majority of SandForce drives that shipped while Crucial suffered used release candidate firmware. Mass production firmware wasn’t distributed until later. And SandForce did nothing to stop it.

The moral of this story is that entering the storage market is still new territory for everyone. Company size, whether small or large, doesn’t dictate whether you’ll face a failure from a new product. The only guarantee you have is the experience of others who’ve used the drives in configurations similar to your own.

Which brings me to todays topic. I’ve been testing Crucial’s fixed firmware and so far things look good. The situation has improved enough to warrant another look at the C300, including its more affordable 128GB version. And that’s exactly what we’ll do today.

The Drive

I’ve explained how SSDs work in great detail here and here, if you’re a newcomer to all of this I’d suggest looking over those articles.

Like most SSD vendors, Crucial turned to a third party to supply a controller for its SSD - Marvell. Inside Marvell’s controller is a pair of ARM9 CPUs that work in parallel. One core handles SATA requests while the other handles NAND requests.

On the SATA side is a 6Gbps interface, a significant upgrade from the 3Gbps controllers found on all other SSDs we’ve reviewed. If you’ve followed our SSD coverage you’ll know that sequential read speed is one area where SSDs are traditionally limited by 3Gbps SATA. The C300 should fix that. To feed the controller Crucial uses ONFI 2.0 NAND with higher max transfer rates.

While the controller is made by Marvell, the firmware is entirely Crucial’s design. As we’ve seen in the past, as long as the controller’s CPU is fast enough the biggest influence on SSD performance is the architecture of the firmware.

Paired with the controller is an absolutely massive 256MB DRAM. The Marvell controller has a smaller cache than what Intel outfits its X25-M G2 with and rather than demand a more expensive controller with a larger cache, Crucial uses a very large external DRAM to store mapping tables and access history. Micron, Crucial’s parent company, being a DRAM manufacturer probably played a role in making that decision.

The RealSSD C300 is available in three capacity points, two of which I’ll be looking at today: 64GB, 128GB and 256GB. The Crucial controller has 8 channels to its NAND. Both the 128GB and 256GB versions have all 8 channels populated, however the 256GB drive physically has more die per NAND package which allows for greater parallelism and potentially higher performance.

Like the Intel and Indilinx drives, Crucial dedicates around 7% of the drive’s capacity to spare area. This non user-addressable NAND is used as a pool of clean blocks to replace dirty ones during normal use, and to replace any bad blocks.

Pricing Comparison
Drive NAND Capacity User Capacity Drive Cost Cost per GB of NAND Cost per Usable GB
Corsair Nova V128 128GB 119.2GB $319 $2.492 $2.676
Crucial RealSSD C300 128GB 128GB 119.2GB $369 $2.883 $3.096
Crucial RealSSD C300 256GB 256GB 238.4GB $660 $2.578 $2.768
Intel X25-M G2 160GB 160GB 149.0GB $405 $2.531 $2.718
Intel X25-M G2 80GB 80GB 74.5GB $215 $2.688 $2.886
OCZ Vertex 2 120GB 128GB 111.8GB $329 $2.570 $2.943
OCZ Vertex 2 240GB 256GB 223.6GB $640 $2.500 $2.862

High end SSDs have dropped in price considerably over the past couple of months. While 100GB SandForce drives were once at or above $400, these days you can get 120GB extended capacity versions for $330. In fact, the price of SandForce drives have dropped so much that there’s pretty much no reason to buy an Indilinx drive at this point. Note that there's no tangible performance difference between the extended capacity SandForce drives and the older versions with more spare area for any of the workloads we'll be talking about today.

Crucial’s C300 is priced competitively with the market, but it does command a price premium over the equivalent capacity SandForce drive. While OCZ will sell you 128GB of NAND on its Vertex 2 for $2.57/GB, Crucial asks for $2.883/GB on its C300.

The Test

CPU Intel Core i7 965 running at 3.2GHz (Turbo & EIST Disabled)
Motherboard: Intel DX58SO (Intel X58)
Chipset: Intel X58 + Marvell SATA 6Gbps PCIe
Chipset Drivers: Intel 9.1.1.1015 + Intel IMSM 8.9
Memory: Qimonda DDR3-1333 4 x 1GB (7-7-7-20)
Video Card: eVGA GeForce GTX 285
Video Drivers: NVIDIA ForceWare 190.38 64-bit
Desktop Resolution: 1920 x 1200
OS: Windows 7 x64
Random Read/Write Speed
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51 Comments

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  • strikeback03 - Tuesday, July 13, 2010 - link

    Really? I have 3 computers, and can see a use for the 30-40GB, 60-80GB, and 100+GB size drives depending on which system I am thinking of. For my HTPC, a small drive would be fine, all it holds is the OS. For my desktop, I have an 80GB X25G2, as IMO a smaller drive would be iffy when 2 operating systems are installed on the drive, and allowing for extra spare area. For my laptop I wouldn't consider anything under 100GB, as I don't want to have to carry a separate external drive to store stuff to. Reply
  • erple2 - Tuesday, July 13, 2010 - link

    I'll second that - my laptop has the 160 gig Intel G2 drive in it because I have installed slightly more than the OS on it (a few steam games + WoW = need more than 80 gig).

    I don't need more than about 120-160 gigs on my laptop (that's what my home server is for). My desktop would be in the same boat - I'd need enough "space" to install some large applications on it plus the OS.

    I've heard people recommend that you should install applications on spindle drives, but the reality is that some of those applications are very slow loading on a spindle drive.

    Personally, I don't care if my OS takes 5 minutes to boot. I almost never shut down anyway.
    Reply
  • neoflux - Tuesday, July 13, 2010 - link

    Fantastic article as always, Anand. Informative, investigative, and conclusive. I couldn't ask for anything else ( other than the funds to purchase a Vertex 2 :P ). Reply
  • Slaimus - Tuesday, July 13, 2010 - link

    With such a large DRAM cache, is there greater risk of data corruption when there is a power outage or power supply failure? Reply
  • Anand Lal Shimpi - Tuesday, July 13, 2010 - link

    Crucial claims to store very little user data in the external DRAM, it's mostly to give the firmware room to store mapping tables and history data to make better decisions about how to organize future writes.

    Take care,
    Anand
    Reply
  • GourdFreeMan - Tuesday, July 13, 2010 - link

    Have you ever actually put this to the test, though?

    Intel claims they do the exact same thing with their DRAM, yet I have had applications that were not in use become corrupt after a sudden power loss (i.e. bluescreen after resuming from hibernation, cat depressing laptop power button) on my Intel G2 drives. The mechanical drives that were in the exact same system prior to being replaced by SSDs only lost minimal amounts of data (and typically only the data in use at the time) under the exact same power loss scenarios.
    Reply
  • Echo147 - Tuesday, July 13, 2010 - link

    My first SSD - And it couldn't be picked up after just 5 hours. Pretty crushed :s

    It'd been shipped with Firmware 0001 which I'm guessing was a large oversight by Crucial or the retailer. I wasn't about to go flashing a £500 drive, so it's in RMA as we speak.

    Will be waiting for Intel's 25nm offerings before dipping my burned toes again...
    Reply
  • greggm2000 - Tuesday, July 13, 2010 - link

    Anand,

    Are there any plans to test these drives in RAID configuration? You've already done so with Intel's cheapest value drive, but for those of us who are considering in the higher end drives, it would be interesting to know such things as will a pair of Crucial RealSSD 128GB drives on SATA outperform a single 256GB on SATA 6Gb... or even how well 4 of the 64GB drives compare as well. Also, how do the Sandforce drives compare in RAID to the others.

    Thanks! Great article as always!
    Reply
  • mckirkus - Tuesday, July 13, 2010 - link

    Just to get a sense of what is used by most humans (hard drives, not VRaptors). Reply
  • Alkapwn - Tuesday, July 13, 2010 - link

    Do SandForce controllers suffer when BitLocker is enabled? I'm guessing there would be less predictable data patterns for it's controller to use, and thus might be slower? Would that then solidly put the lead in Crucials favor? Reply

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