Hello everybody, hello Fernando,

I stumbled across an interesting curiosity: I have a Dell T3600 workstation with Intel’s X79 chipset platform. In order to improve its performance I ordered a Samsung 850 EVO SSD (250GB). Before ordering I called Dell ProSupport and they confirmed that there shouldn’t be any problem using a SSD instead of an ordinary HDD. Also a non-Dell SSD should work without any problems.
I connected the ssd to one of the two SATA3 ports (SATA0) which run in AHCI mode. Additionally there are three separate SATA2 ports which run in RAID/SCU mode (Intel(R) C600 Series Chipset SAS RAID (SATA mode)). Afterwards I installed Windows 7 SP1 x64 and the latest chipset “driver” provided by Dell.com . This installed a newer Intel driver for the Intel AHCI controller than the Windows 7 SP1 media did (why AS SSD Benchmark detected it as MSAHCI – I don’t know). Due to the fact that the Intel chipset “driver” doesn’t contain a C600 SAS RAID (SATA mode) controller driver, it didn’t get installed of course.

Benchmark results look fine so far:



To get the SAS RAID ports working I installed the latest IRST enterprise drivers provided by Dell (3.7.4.1004).


Unfortunately write speeds were tremendously slow and therefore I tested only sequential read/write and access time (read access time was “normal” but write access time took 10(yes, ten) ms!):




I also tried a Liteon SSD by Dell (256GB). Read AND write speed (seq.) were both at about 300MB/s. That means the seq. read rate was very slow (it can do nearly 500MB/s as you can see later on) but seq. write speed was much more better compared to my Samsung SSD (~95MB/s).
Moreover I tried a newer RSTe version by Dell (3.8.0.1108 provided for Dell T3610) and v4.1.0.1046 (Win-RAID). Every time write speed was about as worse as with Dell’s v. 3.7.4.1004.

Thanks to Fernando I found out that X79 chipsets in AHCI mode are also compatible with Intel’s IRST (without enterprise) driver v13.1.0.1058. So I reverted from IRSTe to IRST (regarding the AHCI controller) and used the IRST-e driver only for the C600 RAID controller. Now both SSDs (Samsung & Liteon/Dell) showed their real performance:






How is that possible? Why are write-speeds and write access time so enormously slow? I am not the only one...seems like an incompatibility between T3600 boards<>IRSTenterprise<>SSDs :

https://communities.intel.com/message/221707


Already tested/done:
- latest BIOS
- different SATA ports
- tried another Samsung 850 SSD
- Dell Support (they have no idea...)

Thanks in advance.

Okay, but that's no explanation for the extremely slow write speed & write access times... . That benchmark results differ with every different driver release/version is clear - however this is no explanation in my special case! Look again at the write speed in my third screenshot

Erm, why should I do this? I did nothing except installing one driver after the other.

1) Windows SP1 install (without driver integration at the beginning)
2) installation of chipset "driver" from Dell.com
3) Reboot
--> first AS SSD benchmark run --> everything fine (seq. write speed 473MB/s)
4) IRST enterprise 3.7.4.1004 (from Dell.com) driver installation (including console)
5) Reboot
--> second AS SSD benchmark run --> seq. write speed dropped from 473 to 96MB/s

But why? I didn't change anything else... this is why I'm heavily surprised

Intel won't say anything as my link above shows. They will point to Dell. And Dell can't help atm... they are still looking into it.

I hoped to find somebody else who knows about the issue. I think my solution is a workaround and not an "official" solution for business use.

Thank you for your post, I too am experiencing SATA II performance speeds on one of my two T3600 systems and I cannot seem to find the driver you mentioned installing to get your SSD to perform at SATA III levels, can you please provide a link to the driver?
Thanks again,

avpw2kpro

Thank you Fernando, you wouldn't happen to know how I go about updating the drivers to just RST (not e(Enterprise)) ? As stated by pustekuchencake "Thanks to Fernando I found out that X79 chipsets in AHCI mode are also compatible with Intel’s IRST (without enterprise) driver v13.1.0.1058. So I reverted from IRSTe to IRST (regarding the AHCI controller) and used the IRST-e driver only for the C600 RAID controller. Now both SSDs (Samsung & Liteon/Dell) showed their real performance:"