Hello, I have a RAID 5 array of four 500GB drives, I just bought the fourth drive yesterday because it was on sale. It took over a day to add the drive to the array and it seemed like it worked but in windows the C:\ drive still says it's 931GB when it should be 1.36TB. The Nvidia control panel detects the array as 1.36TB and HD Tach detects it as 1.36TB but Windows doesn't. I have a Asus P5N32-e SLI motherboard and I am using the onboard SATA RAID. The first three drives are Seagate Barracudas 7200.10 and the new drive is the same brand except it's a 7200.11. Anyone know what's going on? Also after adding the new drive HD Tach reports the speed as a lot slower. This is before adding the 4th drive: This is after: What the hell is going on? Any help is appreciated. I really can't afford to reformat and configure the array from scratch, I have way too many large projects that simply can't be backed up.
Youll need to extend the partition to make use of all of the space. Google "diskpart" Your average read speed is about 10MB/sec faster, so I wouldn't worry about the slower burst speed. HDTach is a bit of a pants benchmark for RAID volumes. I would imagine you're nearing the upper limit of the RAID processor anyways.
Thanks a bunch! I'm looking in the disk management and there is 465.77GB of unallocated space, I'll try that diskpart program.
Damn, it turns out Diskpart can't extend the boot partition. Apparently Partition Magic will do it but I really don't feel like shelling out any more money than I already spent on this new drive. Does anyone know of some free alternatives that will extend the boot partition?
Wasn't there something about there being a chipset limitation when comes to reading the true size of RAID array drives? I seem to recall something about this somewhere recently, I'll try and see if I can find it again.
Well I wouldn't say it's necessarily bad to have your boot drive on a raid 5 volume, but it can also not be a really good idea at the same time just due to the extra crap you have to do to get an OS to boot off of raid each time you have to reinstall. Personally I decided to not bother with all that crap and just tossed in another smaller drive by itself to boot off of and then had all 5 of my 500GB drives by themselves in a raid 5 volume so if the OS gets hosed I can just wipe and reinstall and not lose anything on my raid setup. I've also never been too terribly fond of the on-board raid chips on motherboards as they tend to be in a bit of grey area as to whether it's a hardware or software raid chip (I know that sounds odd, and that might not even be the case anymore) which is why I went with a PCIe addon card to handle my raid volume.
The performance characteristics of RAID5 and the access patterns of an OS drive don't tend to get along very well, especially when not using a discrete controller. Its not only a lot simpler to use a single disk (or RAID1 if you really need the redundancy) for an OS drive, it can be a lot quicker too.
Ah ok. I see what you guys mean. I do plan on getting a proper RAID controller at some point it's just that the nice ones are a bit expensive. Eventually I probably will get my OS off the RAID but right now that is not possible. I did get the partition figured out though, a program called Acronis Disk Director extended it flawlessly. Thanks for the advice and help!
