There is a place in the GUI to turn on write caching, but I suspect that it is ignored if the battery is not present.
Also, one more update: Just adding the battery to the 256M card, I got pretty good speeds, but they were erratic (like something else was using the drive). -----Original Message----- From: Micheal Espinola Jr [mailto:michealespin...@gmail.com] Sent: Thursday, February 26, 2009 3:18 PM To: NT System Admin Issues Subject: Re: HP RAID5 P400 SATA questions Im coming in late on this thread, but it sounds like no caching without the battery. -- ME2 On Thu, Feb 26, 2009 at 1:55 PM, Alverson, Tom (Xetron) <tom.alver...@ngc.com> wrote: > Breaking News: I got the memory/battery upgrade for the P400 and > installed both (512MB memory card replaces 256MB card) and has the > battery added. The RAID5 speed is through the roof. I was getting 2 > MB/sec with small block sizes. One a standard desktop drive I get > around 4000 MB/sec with small blocks. With the memory upgrade and > battery added, I got 28000 MB/sec with small block sizes. With large > block sizes I got several times the raw speed of a single drive, like > you should. For large block sizes the RAID5 array had 370,000 MB/sec > write speed and 586,000 MB/sec read speed. > > I then kept the 512MB card installed but removed the battery. The write > speeds are back in the toilet. I am going to try just the battery next > for my amusement, but I have decided that the "stock" P400 card with > 256M and no battery is only good for mirroring, not for RAID5. > > Tom > > -----Original Message----- > From: Glen Johnson [mailto:gjohn...@vhcc.edu] > Sent: Tuesday, February 24, 2009 9:51 PM > To: NT System Admin Issues > Subject: RE: HP RAID5 P400 SATA questions > > Tom. > I am very interested in the outcome of this as I have 5 servers on order > and 4 of them will have this same controller. > I forwarded the first email from this thread to our rep to see if he had > heard anything and asked if we should be concerned. > He said he would do some checking and let me know what he learns. > I'll let everyone know if he shares anything of value. > I sure hope it is something that can easily be fixed as it may be too > late for us to change the order. > Thanks. > Glen. > > > > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ > ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ > > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~