3x Samsung 840 Pro raid-0 performance

I added a 840 pro to my raid-0 config to "break" the as ssd 2000 points barrier.
sadly i did not succeed.
config: win8.1, 3x 840 pro 256gb raid-0 stripesize 64kb, rst 12.8.11.1000 and 13.0.0.1098
Any suggestions to improve the 4K-64 reads and writes?
tyia

as-ssd-bench Intel Raid 0 Vol 26-3-2014 13-47-18.png

You cannot run 2 different RAID drivers simultaneously. Which one was installed?

Not really, since I assume, that you already have realized all options to boost the RAID0 performance.

C-states disabled?
Why 64k stripe size? for me 128k gives best performance, with similar HW.

EDIT: Win 8.1 Maximus 6 Gene 2xSamsung 840 Pro

as-ssd-bench13.png

Tested with both driver versions
Stripesize 64kb is more used?

C states disabled yes sir

Pacman which bios settings are important in your opinion?

For RAID performance i only disable C-states in the BIOS, about stripe size though, i have had some different SSD RAID setups, and i have tested pretty much all of them with 16k to 128k,
and 128k has Always given best scores, in benchmark software that is, can’t say i notice the difference in normal usage though.

Thanks.

My setup is pure uefi.
Could that be the cause?

Overthinking the answers i think we do nog have pinpointed the real problem.
Pacmans as ssd score with 2 drived is better than mine with 3.
The stripesize can not account for that huge difference; i have seen scores of 2900 with 3x 840 pro.

No, there is no performance difference between LEGACY and UEFI mode.
Maybe you have some performance eating applications (Magician, Antivirus etc.) or Services (RST etc.) running in the background.
You should run msconfig and the Task Manager to find it out.

@Fernando :
without magician etc same results.
with rst drivers 12.9.0.1001 slightly better result, but still not satisfying.
left image is actual score with 3x 840 pro; the right one is with 2x 840 pro.

as-ssd-bench Intel Raid 0 Vol 27-3-2014 08-05-19.png

as-ssd-bench Intel Raid 0 Vol 22-3-2014 11-03-47.png

I reset the bios of my M6F and did only basic config.
This resulted in a 2015 score.
Then i configured the bios the way i always do, resulting in the score below.
I leave it for now; thanks for your attention.

as-ssd-bench Intel Raid 0 Vol 28-3-2014 08-57-10.png

proc to 4.6 ghz and running orthos at same time, score is little bit higher (but not satisfying)

as-ssd-bench Intel Raid 0 Vol 7-5-2014 12-58-51.png

without overclocking using rst drivers 13.1.0.1058:

as-ssd-bench Intel Raid 0 Vol 7-6-2014 07-33-58.png

Looks good with 13.1.0.1058

This driver runs very well on my system too.