RAID Card issue

Hi,

I recently purchased 3x HDElements with RAID Cards and have been extremely happy with them. Until Friday when I noticed something funny.

I have two exact same systems running 2 of the HDElement units. The specs are ASUS P6T MB, Core i7 920, 12 GB of RAM, 1x 150GB 10,000 RPM system drive, RAID Card with HDElement and then 4 Internal disks connected via the Mini SAS to SATA cable in the following configuration - 3x disks in RAID 0 and 1x disk as a JBOD. Both running Vista 64 bit. The RAID Card is in exactly the same slot in both systems and built in exactly the same case. HDElement 4TB unit in RAID 5.

Ok, now the issue. On the one system on the HDElement, I get read/write speeds of 310/270 mb/s and on the RAID 0 I get speeds at around 230/220.

But on the other system I get speeds of around 260/250 on the HDElement and around 190/180 on the RAID 0.

The cards are running the exact same drivers and BIOS and the only differene I have noticed is that the card that gives me slower speeds are running about 10 degrees hotter.

Could the difference in temp and speed indicate a possible fault on the card? Would this mean I'm at risk of losing the card? Any way for me to test the stability of the RAID card?

What else could cause the difference in speeds on the cards?

Thanks.