Adaptec ASR-2820SA in Raid0 slower than SW-Raid0
 

Hello everybody.

I got a system with an Adaptec ASR-2820SA with four 150GB WD Raptor's.
I'm using a 256k Chunk for the HW-Raid0 on this controller.
Best speeds I got was between 240 MB/s and 267 MB/s. Yes, that's kinda fast, but wait until I'm finished.

I'm using the aacraid Module, cos after I build that driver into kernel, the box won't boot. It doesn't find the system disc on the Intel Chipset anymore ("sda gone"), but with aacraid build as module, it works "like a charm".

Anyway, I added those four discs to the Intel Chipset and made a SW-Raid0 with 256k Chunk.
Speeds are between 376 MB/s and 411 MB/s, which is odd, isn't it?!

Could the Adaptec be slower cos I loaded the drivers as module? Or what could cause it?

Thanks for any hints! :)

Regards