nvidia raid5 - is it worth it?

[tfboy]

I'm about to build a system for my old man and the asus M2N-SLI-DLX which uses the nvidia 570 chipset.

I'm aware the RAID on these motherboards use the CPU to work out parity. The CPU will be a dual core AM2 (lower end to not break the bank). I would have thought that a CPU like that one wouldn't be constantly hammered for parity calculations when the hard drives are caned? I.e. is it possible that the CPU will be the bottleneck or will it still be the drives?

However, I'm trying to get an idea whether the extra resilience offered is worthwhile. Obviously 3 drives will make more noise and heat than 1. I know 3 is the bare minimum, but is it considered that using only 3 drives doesn't make the benefits really stand out ? Put another way, does anyone have any performance figures or experiences with RAID5 using 3 drives? I've done a search and people saying "my system loads BF2 uber quick" doesn't really help

Any input appreciated.

P.S the alternative is just get one single bigger drive. Easier to maintain, less heat / noise but no resilience... Arguably, as it's a workstation and not a server, and because all the data will be backed up, maybe the cost and technical complications for his usage (office work + music and video editing) don't make RAID worthwhile?

[kalniel]

Single disk.

Unless you need access 24/7 even during loss of drive (which is where raid 5 etc really shines) then the reduced cost/complexity of a single disk make it the preferred solution.

[CrimsonAvenger]

Agreed - single disk for the better solution, esp. as your backing up the data elsewhere.

RAID 5 will give lower performance than a single disk or RAID0 array.

Remember also that you'll lose approx. a third of the total disk space when using Raid 5 also.

[5lab]

raid 5 gives a boost in both performance and security. basically you need x+1 disks (x>1) and you get x*single drive capacity. its good for servers etc, but you need array monitoring software to have an advantage. i'd say for a home pc its waaaaaaay ott.

[shaithis]

RAID 5 is great if you can afford it and you hate taking backups frequently

I have been RAID5 for almost 3 years now, in that time I have lost 2 drives but no data or downtime

Still, I would always use a quality add-in card, I had 3Ware before but recently switched to the Areca PCI-E card which is like the proverbial ****e-off-a-shiney-shovel

[tfboy]

RAID 5 will give lower performance than a single disk or RAID0 array.

and

raid 5 gives a boost in both performance and security.

Have you used raid 5 offered by an nvidia chipset? Sounds a bit contradictory to me!

I know the theory and that I'll lose a drive for parity so no extra storage and all that. I just wanted to hear of anyone with real experience using the raid 5 functionality offered by the nvidia chipset.

[tfboy]

Thinking about it, phrased differently, is there a significant performance increase with RAID 5 over RAID 1 mirror considering the extra expense of a hard drive?

edit: Hmm I'm having second thoughts. Found this review: http://techreport.com/reviews/2005q4...d/index.x?pg=1
and RAID 5 performance is quite lacklustre. I just wonder if the nforce 5 chipset makes a stellar improvement. If it doesn't, then there's no point in going RAID 5

I also realise I mixed up RAID 3 and RAID 5, so apologies. I guess I don't lose as much storage capacity with RAID 5 than RAID 3 (parity split across drives as apposed to a dedicated parity drive)

[tfboy]

OK, it doesn't look good.
From AnandTech's mention here: http://www.anandtech.com/cpuchipsets...spx?i=2764&p=5

However, the performance results during our RAID testing found no measurable differences between the nForce4 and nForce 500 storage systems. In fact, the less than stellar write performance of the nForce4 in RAID 5 continues in the "new" chipset.

Sounds like I'm better off avoiding it.....

[-ChEM-]

read speed are as very similar to raid0

write speed for small files are poor especially if you arent prepared to defrag regularly

when youre going through the nf5 controller you are going to lose cpu time as it has to process all the drive reads and writes and calculate the parity... im sure you can find nf5 reviews that look at cpu utilisation with raid5 to give you some idea... as for your question, it seems a bit backwards, the cpu wont ever be the bottleneck but that seems a bit flippant in terms of how much you care about wasting cpu time, if youre doing audio/video editting you will need it for that more than you need it for HDD access

and the main difference between raid3 and raid5 is that in raid3 you have one drive getting caned because it is written to whenever any one of the other drives is written to as the parity need to be recalculated... this makes one drive hotter than the others so it dies quicker, but with raid5 the parity is spread to give an even load across the disks, speeds are the same and so is wasted data (just because its spread doesnt mean the parity takes up less space)

i would just get a decent drive and make sure theres enough ram and cpu power there to handle the heavy stuff, only the video editting requires enough HDD reading for it to really matter and even then its not that important

and if you really want security you can just make a raid1

[Jinx]

Try this review from Hexus on the XFX Revo (3-port version)......Raid 5 add-in card.....compares it to chipset based as well.

linky

[chuckskull]

For a home system for your old man. Single disk. Simpler, safer and cheaper.

Unless of course your dad is a FPS addict and you didn't mention it Just get one 250gig drive for £50(ish) and he'll never run out of space.

[aidanjt]

BIOS RAID + RAID5 = PANTS...
Just avoid it entirely.