Are you getting ready to build a new PC and trying to figure out which hard drive to get? Have you always heard your friends talk about the “10k Raptor” from Western Digital as the defacto fast hard drive to get regardless of if you are putting together a work or gaming machine? Does the 150GB size of the drive and pricey $160 sticker price make you second guess yourself? Now let’s say you find a hard drive you want, do you do RAID or no RAID?
These are excellent questions, and we are going to answer the shit out of them them for you…
Raptor All The Way… Right?
First off, since the early 90s I’ve been a die-hard fan of Seagate. I’ve had 2 Western Digital drives fail on me (years ago), 3 IBM Deskstar drives (now Hitatchi Deskstar) and 1 Maxtor all fail on me. Fortunately I’ve never had a Seagate fail on me… although… I do have 2 friends that between the two of them have had something like 5 Seagates fail on them. Fortunately they were all OEM drives stuffed into Dells so I’m secretly praying in my heart that the reason they failed is because they were bargain-bin/non-QA’ed drives stuffed into low end Dells (non-XPS machines). But take that for what it’s worth…
The only reason there is even a conversation to be had “Western Digital or Seagate?” in my opinion is because Western Digital did a smart thing and created a 10k RPM fast-as-hell drive that just blew the doors off all of the IDE and SATA-based drives for years… more or less since 2004 the Raptor and now Raptor X have been the drive to get. The down side is that you will pay about $1/GB for the drive, and the performance, while nice, isn’t mind-bending.
In the last year or so Seagate, Maxtor and Hitachi have been making their SATA drives faster and faster, although still spinning at 7200RPM. The reason for this is that Seagate bought Maxtor and Seagate already has the top-of-the-line enterprise/SCSI drives that it offers, so it’s not going to want to eat into that market with fast/cheap SATA drives. Also Hitachi bought the Deskstar series from IBM years ago, so my guess has to be there that they don’t have the engineering to create enterprise-level disks like WD or Seagate can.
Seagate Bumps up Performance with Technology
Anyway, to get back to the problem… when I went looking at drive speeds recently I noticed that Seagate had released it’s 2nd generation perpendicular recording hard drive, the 7200.11 series. The 7200.11 series started off with the 1TB drive, then they back-released the 750GB and 500GB sizes. Since I’m a long-time Seagate fan and didn’t want to jump on the Western Digital Raptor X without seeing what Seagate had in store, I started to dig into benchmarks and reviews.
One of the reviews I ran across of the 7200.11 was over at HotHardware. They had a chart up that showed the 7200.11 dominating the first-gen Raptor (not the Raptor X, which is 5-15% faster than the 1st gen sibling):
the key to take aware from this diagram is the 81.8 MB/sec average (not burst, but average) transfer rate. To help explain why the 2nd gen 7200.11 are so much faster we look at the big changes Seagate made:
- With the 7200.9 series Seagate added “NCQ” or Native Command Queuing. Basically the drive could intelligent order data requests to optimize the physical movement of the heads across the platter for faster access times.
- With the 7200.10 series Seagate switched the drives to using the new perpendicular recording design for the platters and the bytes on them. This again increased access times and data rates.
- With the 7200.11 series Seagate fine-tuned the perpendicular design and added a 32mb cache to the hard drive, up from the previous 16mb cache that had been on the drives since I think the 7200.8 series.
The most pressing reason for the boost in speed was due to the perpendicular recording, which looks something like this:
the physical distance between bytes of data are much smaller and can be accessed more quickly.
Western Digital or Seagate?
Now for the astute folks in the crowd, you’ll notice that the performance of the 7200.11 is no on par with the Raptor, but not beating it. So why should you care? Well for starters the 500GB 7200.11 from Seagate is $119 while the 150GB Raptor X is around $175. That’s more than 3x the drive space for $40 less, which is important in this day and age of video/music/porn. You need your storage!
In all honesty this decision is really up to you. I’ve presented the facts (performance and price) and you need to decide what you need. Maybe you don’t need that much space and you hate Seagate… well then get the Raptor. Maybe you need a lot of space, well then the Raptor is off the table just because of it’s smaller size. Either way, you decide.
Now… 6 months ago this section would have never existed… but a friend of mine, Marc Chung, built a ReadyNAS NAS for his network. After he did that and told me about it, I decided to do the same. One of the big decisions you have to make with a NAS, is which drives do you stick in them?
Being a Seagate fan himself and wanting huge storage, Marc did some research and found an interesting bit of data. Seagate actually makes an enterprise version of it’s standard SATA drives that are labeled with the moniker “ES” or “ES.2″ (their serial numbers have the initials “NS” in them).
These drives are rated and tested for higher hours of operation than the standard “AS” drives that most consumer PCs have in them. Fortunately enough, these ES/ES.2 series drives don’t carry much of a premium… sometimes as low as $20 more for the same size drive, or in the case of the 500GB 7200.11, it was $40 more.
I ended up buying 2x750GB ES drives and putting them in my NAS, and after more than 6 months of operation the SMART+ data on the drives reports things humming along well. Because of this, I would actually say if you went with the Seagate, to get a more reliable experience, you might consider paying a bit more and getting the EC.2 series of the drives. After all, it’s still a hell of a lot cheaper than the Raptor.
Do I Use RAID or Not?
Ok now let’s say you decided on which hard drive to get, and now you are wondering if you should use RAID or not to get some extra umph out of your storage system. For a quick reference, keep this in mind:
- RAID 0: Even number of hard drives all act as 1 hard drive to split work across all at once. Most performance, least reliability. If any drive fails, you loose all your data.
- RAID 1: Even number of hard drives where half of the hard drives are used to mirror the contents of the other half so you always have a working copy of everything. Some performance improvements with read operations can be made if the RAID controller supports it. If any drive fails, the controller will fall back to the backup copy of the disk until you replace the broken drive.
- RAID 5: A sort of compromise between RAID 0 and RAID 1, usually a 3-drive setup where disks 1 and 2 act like a RAID 0, and disk 3 contains a parity of the contents on the 2 drives incase either fail. If a disk fails, it can be replaced, and then it’s contents can be rebuilt from the contents of the 1 remaining data drive combined with the parity drive.
So as you guessed it, RAID 0 is for the performance freaks, but a really bad idea if you have no backup system in place. Luckily for me I have a NAS, so having rolling backups is no problem incase my RAID array fails and I have to rebuild my install of Windows.
So at this point I set out to figure out what a RAID 0 setup with these high performance SATA disks looked like and I found some interesting things…
Back in 2004…
I decided to use the Raptor in a RAID 0 setup as my search criteria as it’s much more likely people put these things into a RAID 0 setup then bragged about them, since they are “t3h ub3r dr1v3!”. If you do that, the first link you will run across will be an Anandtech article from 2004 that shows the RAID 0 configuration proving to be a complete waste of time:
… but I just could accept this data. First off, drives have gotten faster… but more importantly, RAID has been shipping as an on-board feature in mainstream motherboards now for almost 4 years… and on enthusiast motherboards for more like 6 to 8… so in the last 4 years I have to imagine that Intel and others have optimized and refined the logic and performance available from their on-board RAID controllers. Not to mention that the throughput of the system bus that the storage system is on is a magnitude faster now than it was in 2004. I just refused to believe that putting two fast-ass drives in a RAID 0 configuration in today’s world would yield such pathetic results, so I kept digging…
Back in 2006…
Soon I ran across another HotHardware article from 2006 (still old, but more convincing of what I expected) that gave some numbers for a Raptor-based RAID 0 configuration that blew the doors off of a non-RAID setup:
take a look at that and weep. They are looking at almost a 2x speed up with a RAID 0 configuration with a fast SATA drive as compared to the non-RAID setup. These were more the type of results I was looking and hoping for.
RAID 0 is not a sure-fire win though. HD Tach (shown above) is a synthetic test and doesn’t represent a normal application, like loading a game or opening a program. Storage Review has a great FAQ entry on RAID 0 and what type of performance you should expect, when RAID 0 is awesome and when it sucks.
Well that about does it. We hope we’ve provided enough information for you to decide not only which high performance SATA drive you should pick up, but if you should throw it into a RAID configuration or not, and if so, what to expect from it.
If you have any additional notes for us or your own performance numbers to share, we’d love to see them. Thank you for reading!
This section includes some important notes that you might want to file away in your brain as a supplemental to this guide.
- The Raptor X has been out for a while… there have been rumors floating around that Western Digital was prepping a new Raptor that was a hybrid drive including a large segment of Flash ram on it to increase performance. BIDB thinks this rumor might go away, because the huge surge behind SSDs (Solid State Drives) may make the need for hybrid drives totally useless.
- All on-board RAID in most main stream motherboards is actually software-based RAID and not hardware-based. If you desire hardware-based RAID for slightly better performance and better reliability there are a slew of SATA-based RAID cards out there to choose from.
- Having a drive fail on you and loosing your RAID 0 array can and will happen. Don’t ever setup a RAID 0 array for a computer that has mission critical information on it that needs to be backed up, unless you setup some good off-site backup for that machine as well (like syncing every night at midnight with some central backup server).