Also, the Windows Experience Index means absolutely nothing. You shouldn't bother to base anything on that number; the number means nothing, quite literally.
It was me who started the other thread on the almost identical topic (http://communities.intel.com/thread/23608?tstart=30). It looks like we have exactly the same problem and indeed by doing a complete shutdown and cold start the problem goes away. At least until you reboot!
I tried using Intel's "chat" system to report it but that was utterly useless and despite promising to pass it on to someone who could help (as they certainly could not) I never heard anything back. I then tried their e-mail support and got nothing but an acknowledgement. So I phoned their expensive phone number and finally the ball started to roll. They asked for all sorts of information - VAT invoice from the supplier, a number from the casing (as they weren't interested in the serial number that their own tool reported) which meant taking the system to pieces. Anyway, they said someone would get in touch and I now seem to have some kind of case ID. My Intel ref is 8000290527 so if you do manage to get through to them tell them that and it may get them more interested.
I also have the same situation of one firmware being PPG2 and the other PPG4 (mine seems to be "PPG" and yours is "PWG"?) and when I asked about this during the "chat" they said that both firmwares were the latest and the different numbers referred to revisions. In that case I would say the later revision is the newer firmware but they didn't seem to get that. Maybe this is the problem? I used to have reboots that gave me one drive at 6gb/s and the other 3gb/s but lately they both seem to go to 3gb/s after a reboot.
Well, I suggest you call Intel and get a case going and if I hear anything from them I'll post it here. It's good to see it's not a motherboard thing so in my case they can't shift the problem to Dell which I'm sure would have been the first trick they would have tried! Let me know if you make any progress/discoveries too.
You can run WEI on command line to see the underlying benchmarks to isolate the problem: http://technet.microsoft.com/en-us/library/cc770542%28WS.10%29.aspx
I'll follow up with Intel on this curious SATA mode issue.
Many thanks - I've got a case reference number (8000290527) but it seeems I have to take my system to pieces again as they need me to check another number printed on the drive itself!
I also notice that when I benchmark these 2 drives, one is significantly faster than the other in the first part of the benchmark (420mb/s vs 372 mb/s). I have the trim tool scheduled to run once a day but this hasn't levelled out their speeds although I don't suppose it is meant to. The one with firmware PPG2 gets better results and benchmarks using ATTO show the same difference between the drives. I've run the different benchmarks many times on different days and the difference always shows up.The drives are in AHCI mode and the CrystalDiskMark benchmarks are shown below:
Please let me know if you find anything out.
I will share anything I find out.
One new tidbit ... Last night before I went to bed RST reported drive C to have a 6Gbs transfer rate. This morning RST reported the same drive having a 3Gbs transfer rate. I had not rebooted the system between times nor did the system sleep.
Hmm that's a curious one. I haven't found my system doing that. I remember being told by Intel that the tool only reports the situation that exists at startup so that if anything changed post-startup it wouldn't show the change. If your RST has changed its information without a reboot/restart then it means Intel were wrong about that.
I was also wondering if your drives have the same difference in speeds that mine have. One runs at 430mb/s and the other 370mb/s as in the picture I posted above. I used CrystalDiskMark benchmark software (which is free) to get these figures. If you have time could you check your speeds too? I have a feeling the different firmware is behind this.
It just occurred to me that it is Tuesday and Microsoft may have pushed some patches that could have rebooted the system in the middle of the night. I'll chec on that when I get home. I haven't run any benchmarks but I'll look into that as well.
I validated that my system did NOT reboot over night. So, sometime between the time I went to bed last night and woke this morning the transfer rate on Port 0 drive C dropped from 6Gbs to 3Gbs as reported by RST. The following are Crystal Disk Mark results for both drives before and after a power off/on:
Drive C RST reporting 3Gbs before power cycle:
Drive D RST reporting 6Gbs before power cycle:
Drive C RST reporting 6Gbs after power cycle:
Drive D RST reporting 6Gbs after power cycle:
I have yet to call Intel. Do they have a presence here?
Because you're using RST, this makes figuring out if the problem is with the drive itself or with the SATA controller very difficult. Excessive PHY errors could cause the speed to be re-negotiated at a lower rate. These sometimes manifest themselves as CRC errors in SMART statistics.
EDIT: Nevermind. I forgot that Intel SSDs don't provide SMART attribute 0xC7, so determining if there are CRC errors is impossible. PHY errors may be possible to get but you'll need an Intel engineer to provide the low-level details of which SCT page in the drive contains that information and what byte offset.
EDIT #2: I see you're using the on-board Intel controller and not the Marvell. Okay.
The difference in speeds between your 2 drives isn't as marked as mine but am I right in guessing that drive C is the one with PPG(PWG)2 firmware?
It's interesting that you've proved RST doesn't just report the state at boot as the person on the Intel chat insisted. I wasn't 100% sure that they knew what they were talking about anyway!
I think Intel are like Coke - they'll be everywhere. Where are you exactly?
I've now given Intel every single bit of information that they requested - Grandmother's shoe size, colour of the guy next door's car, etc. so they should finally pass the case on to an engineer. I hope to hear from them soon.
You are correct. The firmware for drive C is PWG2 and drive D is PWG4. I will try to contact Intel tonight.
After a quick search it seems that firmware that starts "PPG" is for 120gb drives and "PWG" for 256gb drives. I came across a lot of discussion on a German site about the difference in firmware and speed and also some people in a Mac forum talking about it. I think Intel must be aware of this issue by now but I don't know whether or not this includes the drives changing from 6gb/s to 3gb/s
I opened my own problem record with Intel tonight and she immediately escalated it after referring to yours. She said it typically takes between 24 and 48 hours before someone get's back to you so maybe we'll know something more by the end of this week.