Poor IO on new DL685c

[Stcragg]

I have a strange issue with our SAN. We have a HP c7000 Blade Enclosure, with 4 BL480 G1's and 2 newer BL685c's with 2 HP (Brocade 4024) 4GB FC Switches and attached to this is an EVA4400.

Each Blade has a dual port QLogic FC card (4GB). The performance between the BL480's and the BL685c when it comes to IO differs by over 30% - as in the BL480's are 30% faster than the BL685c's.

The QLogic cards in both models are the exact same type and are running on the exact same firmware - everything appears to be identical between the two models.

The zoning is the same - and i've ran the Brocade SAN Healthcheck report against the FC Switches, with it giving no possible errors or issues to look into.

I'm thinking that there maybe a hardware problem with the QLogic cards in the BL685c's as when i took one of them out and placed it into BL480 the reduced performance followed it, but i'm having problems believing that it's a hardware issue on the QLogic cards as there are two of them giving the same issue.

I've raised this with HP support and all they have said is that as the newer Blades are AMD then they are bound to be slower... yet sticking this HBA into an Intel Blade gives the same poor performance result.

Just looking for a sanity check on this.

Many thanks in advance, for any help given.

Steve