SSD Speed dropped tremendously

Hey guys - I own a Crucial M4 128GB never had a issue until now. I took a member's advice from here and did not install Intel RST driver upon doing a fresh OS installation on the ssd. Previously on CDM My sequential read speed was 400mb+... i dont know what i was thinking but today i installed the Intel RST and now my seq read is only up to 260mb ish... I tried unistalling the RST driver but CDM seq cant go up more than 260mb.

The reason why i downloaded the RST was because right now my SSD is set up as RAID under my bios (not actual raid) and using a 320gb HDD as backup storage. I wanted to switch to AHCI so after reading some info i changed the DWORD in registery (HLKM-Currentcontrolset-service-msachi and set the start for 0 from 3). I did rechange the registry value back to what it was and still did not fix the issue. My guess is that something from the Intel RST driver changed the registry value or not fully unistalled...

Anyone know a way to resolve this? By the way i already have done ALL possible SSD tweaks before this issue im just really bummed - as a last resort i can format/re-install and hopefully that fixes it but i really don't want to take the route

 

RAID and AHCI in the BIOS are actually the same thing as far as the drive speed goes. RAID just enables you to make RAID volumes, such as mirroring or spanning. Any drives not in such an array run in AHCI mode.

Intel RST shouldn't have killed your speeds like that.

How full was the drive when you ran it before with the good speed versus the now lower speed?

Also, what firmware is the drive at? 0001 or 0002? If you have 0002 then Intel RST is fine to use. It just had some issues with LPM under 0001.

 

RAID and AHCI are not the same thing.
In RAID mode the Intel RAID ROM is invoked and the drive is controlled by it.
In AHCI mode it is controlled by the BIOS, maybe by an Intel AHCI ROM(very rare).
In RAID mode one can enable Write Back Cache with the Intel Rapid Storage UI. This is not possible in AHCI mode.
RAID mode does not support TRIM, AHCI does.
If you don't want to use RAID(RAID0 or RAID1), configure your BIOS with AHCI!
I experienced similar drops of seq reads with CDM. But with Anvil Bench mark, ATTO and AS SSD they were not reproducible. After thorough investigation I think this is a problem/failure of CDM.

 

Interesting maximinimaus, and counter to a number of things I experienced with my desktop, though perhaps mine is an odd duck. Not saying you are wrong.

I have both the SSD and a RAID 1 Array of 1TB Caviar Black's on the same Intel controller. The SSD is not part of an array, and TRIM commands pass through fine. I remember reading that setting to RAID was fine for an SSD (at least on my chipset) as long as it wasn't part of any array. Then TRIM would work fine, and speeds would be as expected. Both proved out for my system. But again, it might the exception, not the norm.

I agree however that there is no point in setting RAID mode unless you are to use it.

 

madmattd you're right regarding TRIM support for SSDs that are not part of a RAID array.

Found following information regarding TRIM and RAID in an Intel document

Intel® Rapid Storage Technology
OEM Technical Guide

19.1.2 RAID Mode
19.1.2.1 TRIM on pass-thru disks
The Intel® Rapid Storage Technology driver processes the host ATA Data Set
Management (DSM) TRIM command on any pass-thru disks that support ATA DSM /
TRIM in accordance with the ATA-8 specification.
19.1.2.2 TRIM on RAID volumes
The Intel® Rapid Storage Technology driver does not support TRIM commands on
RAID volumes.

 

Yea, okay, glad to hear I had at least that much right. I knew mine was working...obviously in a RAID array TRIM doesn't pass through, I wasn't trying to say that. I could have been clearer.