Dell PowerEdge 6300 PERC2/QC (Adaptec AAC-364) RAID Controller Battery Replacement

Here's an example of ridiculous attitudes to customer service. The RAID controller has a battery-backed RAM cache (64 or 128MB) but Dell do not supply a replacement battery - they suggest replacing the entire controller!

Dell PERC2/QC aka Adaptec AAC-364 RAID controller

The battery is a trickle-charged NiMh consisting of 4 cells in parallel+series configuration to offer 2.5 volts for around 72-hours of cache protection if something fails. This gives time to move the cache daughter card to another machine with a good controller and allow the cached data to be flushed to the array.

Obviously over time the batteries will degrade. In fact the Windows tools that ship with the server include a battery reconditioning utility and recommendations on when to use it. When they do fail something like this will be reported at boot-time and the array controller will refuse to boot, making the server inaccessible:

Error: Self-test failed
Component: AIC-7815, NVRAM Memory controller
Test: Battery disconnected, check battery jumper.

The battery backed memory module contains valid data that has not been written to disk.
The module needs to be moved to a functional controller to recover data.
Please contact your system manufacturer
Keeping the board in a powered system will extend the battery's holdover time.

Error: Controller Kernel Stopped Running.....

I've had this issue with a PERC 2/QC, aka Adaptec AAC-364. Removing the battery from the cache daughter-board ...

Battery Connection Close-Up

9000MD with battery removed

...I found it measuring around 2.5V but unless the server was left powered down or the battery otherwise exhausted this error would occur on boot.

I cut the battery open to see if it would be possible to replace faulty cells. There are four 1.2v cells arranged in series + parallel so the output voltage is 2x nominal (~2.4) and current is doubled too. One cell showed 1.5v but the others were showing between 1.2v and 1.35v.

Battery Pack (HP p/n D9161-63002)

Through some searching around I discovered that a version of the AAC-364 is also branded HP NetRAID 4M (p/n HP D9351 or D9351A).

I managed to buy one of these complete with BBU and 128MB cache from a computer recycler on eBay for £18 (US$10).

It works as a slot-in replacement. I was intending to replace the HP BIOS (arrived with older V2.4.0 -4584) but after preparing floppy disks and renaming the PERC2 firmware files to the NetRAID convention of NETR4Mxx.UFI it turns out the replacement card has a slightly different PCI revision which prevented using the Dell-branded firmware. I then noticed the HP daughter-board has Adaptec p/n 9001MD whereas the PERC2 has 9000MD.

9000MD Cache Daughter Board

What is nice about the 9001MD is the battery isn't glued - it sits in a metal frame case and has a plastic tab attached so you can pull it up and out. The connector socket and jumper J3 are also on the top edge of the card so the cards don't have to be unscrewed and taken apart.

The new battery shows 2.7 volts when not connected to the load.

Instead of flashing the BIOS I just swapped the cache memory and BBU over.

The BBU in the HP unit has a replacement part number on it:

HP original P/N: D9161-60002 HP replacement P/N: D9161-63002

I found the battery available for  US$127 from and  US$119 from Impact

The  HP firmware update download is here See also the links to  all other HP NetRAID 4M documents.