IOCrest SI-PEX40071 SATA III 8 Port Controller Card PCE-e 2.0 x2 with Low Profile Bracket

After reading the specs of this card and talking to tech support at SYBA, here is what I understand.

1. While the SATA ports on the card is capable of SATA III (6 Gb/s or 750 MB/s, where Gb = Gigabit and MB = Megabyte, and 1 Gb = 125 MB), the maximum speed of this card is limited by the 1 lane of PCIe slot, which depends on the version of PCI Express on your motherboard.

2. PCI Express 2.0 supports maximum speed of 4 Gb/s (=500MB/s) for each lane. So the max speed of this card would be 500 MB/s. This is faster than SATA II (375 MB/s) but slower than SATA III (750 MB/s).

3. PCI Express 1.1 supports maximum speed of 2 Gb/s (=250MB/s) for each lane. So the max speed of this card would be 250 MB/s. This is slower than SATA II.

4. The 4 ports on this card share the same PCIe x1 lane. So if all 4 ports are in use, the maximum speed per port is 1/4 of the maximum speed given in (2) or (3).

I have been able to confirm these conclusion by running the following experiment. I am using a Transcend SSD370 512 GB drive, which is advertised to have max read/write speeds of 560/460 MB/s.

To test this SSD's speed, I plug the SSD into an ASUS P8Z77V-LX motherboard, which has both SATA II and SATA III ports.
In the SATA III ports, the max R/W speeds are 504/457 MB/s, as measured by CrystalDiskMark 3.0.1
In the SATA II ports, the max R/W speeds are 275/262 MB/s.

Now, I plugged the SSD into the PEX-40064, and put it into the PCIe x1 slot, which is compatible with PCI Express 2.0. The max R/W speeds are 385/286 MB/s

So, the PEX-40064 is capable of delivering a higher speed than SATA II, but far from SATA III (read on if you have PCI Express 1.1).

I ran the same tests on an older motherboard -- Gigabyte P35-DS4, which has only SATA II ports and supports PCIe Express 1.1
In the SATA II ports, the max R/W speeds are 260/254 MB/s, similar to those in the SATA II ports of the newer ASUS board.
I then plugged the SSD into the PEX-40064, and put it into the PCIe x1 slot of the older P35-DS4 board: The max R/W speeds are 202/168 MB/s
Indeed, the PCI Express 1.1 slots are slower than the PCI Express 2.0 slots and the SATA II ports.

Conclusion: Where does this leave us?
-If you have a motherboard that has SATA II ports (but no SATA III ports), and you have PCI Express 2.0 slots, then you can use the PEX-40064 card to get a faster speed (if your SSD can achieve it) but you will not get close to SATA III speeds (even if the SSD is capable to achieve it).
-If you have a motherboard that has SATA II ports but no SATA III ports, and you have PCI Express 1.1 slots, then you are better off using the SATA II ports than the PEX-40064 card.
-If you are using the older magnetic spin hard drives (HDDs), then this discussion is not relevant. Most of my HDDs rarely achieve sustained R/W speeds above 100 MB/s.

-In my experience, the PEX-40064 card tends to freeze up in the PCIe 1x slot when I transfer large amounts of data (more 10 GB). But if I put the PEX-40064 card into a PCEe x16 slot, I rarely encounter freeze up. I don't know how to explain this, since the card uses only 1 data lane, regardless of how many data lanes are available in the PCIe slot. I ask tech support about this but I did not get an explanation.

Hope all of this is helpful.

AFTER THOUGHT: To get faster than SATA II speeds for motherboards with PCI Express 1.1 slots, here is what I would do. Switch from the PEX-40064 card (which uses 1 PCIe lane) to the PEX-40054 card (which uses 2 PCIe lanes). This turns out to work !! The Transcend SSD370, plugged into a PEX-40054 card in a motherboard supporting PCI Express 1.1, has the following max R/W speeds: 373/285 MB/s. This is almost the same as the PEX-40064 card with PCI Express 2.0. The only downside is that the PEX-40054 works in a PCIe x4, x8, or x16 slot, but not in a PCIe x1 slot.

SECOND AFTER THOUGHT: It is possible to achieve close to SATA III speeds in a motherboard with PCI Express 2.0 slots with more than 2 data lanes (e.g. x4, x8, or x16) with the PEX-40054 card instead of the PEX-40064 card. For the Transcend SSD370, the max R/W speeds are 479/458 MB/s, very close to the speeds of the SATA III port in the new ASUS board.

If you are looking at this card you probably want a card which will allow your SATA 3 hard drives to function on an older SATA 2 motherboard. The good news is this card will do that (at least for me on Win7 64bit). The bad news is there are many variations of the PCI-E interface and this card based on the Marvel 88SE9215 which is only an X1 device. That means that you will only get a single channel for your data (X1) and that the ability to get a SATA 3 speed is greatly reduced. For example, my SATA 3 Samsung 850 EVO SSD should be getting > 500MB/s but on this 88SE9215 controller I am only getting an average of 333MB/s. Technically, the speed I am getting is > 300MB/s so it can be called SATA3, but barely.

What you want is the other IO Crest card in this group based on the 88SE9235. It is only a few bucks more but is an X2 device and should allow more data flow closer to 500MB/s. I'll update this when I get the 88SE9235 installed.

++ UPDATE ++
Removed 88SE9215 and installed 88SE9235 (which is X2). Once I got the drivers installed, the transfer rate stabilized and my Samsung 850 EVO SSD averaged a transfer rate of 425 MB/s. I'm pretty happy with that.

To recap, 850 EVO SSD - SATA2 motherboard connectors= 245MB/s, 88SE9215 (X1) = 333MB/s, 88SE9235 (X2) = 424MB/s.

Bought two of these controller cards to use when upgrading my NAS4Free box for the first time in 5 years. Using with Asus B85M-G R2.0 motherboard. Plug-and-play with NAS4Free, no complaints.

Edit (3/8/2013): The description for this product states that it doesn't support SSD drives, but my Crucial M4 64GB and now my Kingston Hyperx 3k 250GB SSD drives both work wonderfully on it.

Let me give a little background. I originally bought a Crucial M4 64GB SSD drive so I could give my new gaming rig the extra push that I always wanted. After installing the SSD to my 1 year old ASUS motherboard, I noticed that my speeds weren't quite what I was fully expecting, even after tweaking and Q&A'ing the support forums. It was narrowed down to my motherboard which contains a simple AMD 880G chipset with SATAII connections. While this is perfectly fine with ordinary hard drive, it becomes a bottleneck for SSD's.

That scenario led me to this product. I sought for a way to gain SATAIII connections without replacing my current motherboard. This product does just that. I made sure I had an empty PCIe x1 card slot open and checked the specs and reviews. Shipping and packaging was good as always. Installation was easy and I downloaded the latest AHCI drivers from the manufacturers website ([...]). Installing an ordinary hard drive to this is not going to give any performance increase, but it is definitely worth the investment here. I can recommend this for anyone with SSD's with a slow chipset (mainly AMD's). As evidence below, I recorded a 35% increase in performance via total score. Easily worth a $20 investment.

For those interested, this PCIe performs on par with the Marvell controller.

Results of AS-SSD benchmark testing:

Using SATAII 880G chipset slot:
Seq:
Read 255 MB/s
Write 109 MB/s

4K:
Read 19 MB/s
Write 42 MB/s

4K-64Thrd:
Read 150 MB/s
Write 89 MB/s

Acc time:
Read .132 ms
Write .259 ms

Score:
Read 196
Write 143

Total score: 438

Using Syba SATAIII slot:

Seq:
Read 366 MB/s
Write 110 MB/s

4K
Read 23 MB/s
Write 72 MB/s

4K-64Thrd
Read 216 MB/s
Write 97 MB/s

Acc Time
Read .102 ms
Write .257

Score
Read 276
Write 181

Total
594

So far so good. Here's my procedure as some had issues installing drivers and or on Windows 10. I installed the card in an available slot, I didn't plug in any SATA cables yet, left original hard drive still connected to original location and then started windows 10, After booting into Windows for a few minutes I did another restart not plugging in any drives. After booting into Windows a final time I did a final shut down and plugged in the hard drives SATA cable to this new card, I then went into my bios and re-chose to boot first my SSD drive. My motherboard is a Asus Rampage II Extreme, it is only SATA II so I get maxed out at 270 mb/s read/write speed. Upon first test I got around 550 mb/s after installing this card!!!! very much improved. I never installed any drivers from disc with me booting with the procedure above I let windows choose the appropriate and best one. I included a photo of my new speeds! I will do more testing but it is clear that I doubled my speed of my newly purchased SSD a Samsung Pro 256 Gb. I'll update later to see how it works long term. It is definitely snappier opening programs and multitasking.
I am very happy so far with the product. I also did a bench test on my video card to see if sharing of resources of the PCI lanes was an issue and it was not. I get same scores on my video card benchmarks as before maybe a bit better too. :)