I recently went ahead and exchanged the p400 RAID controller in my HP DL380 G5 server with an LSI HBA card (SAS 9207-8i). I did this to get better disk compatibility, and I didn't need RAID functionality. I popped a few Samsung SSDs in the machine and they where perfectly recognised.
The only issue I am having is that the HDD LEDs aren't working anymore. They quickly flash when I power on the server, but afterwards they do not blink on disk activity. Before I started using the HBA card, it was blinking on disk activity. Is there anyway to fix this?