What is the fastest Harddrive for my Home PC? SAS or SATA?

July 10, 2008 3:04 PM

What is the fastest Harddrive for my Home PC? SAS or SATA?

I've closed my eyes on the harddrive technology scene for half a second and it all seems to have changed.

I want a new hard drive for my home pc ive got about £100 to blow

From what i can tell SAS drives are now the fastest, and better than SATA 2 (or is it 3 now?)

Is my ASUS A8N32-SLI-Deluxe motherboard SAS harddrive ready?

if it is im looking at getting a seagate cheetah at 15krpm

if it isnt ill look at a wd raptor 10k rpm

posted by complience to computers & internet (10 comments total)

If you look at the spec sheet for your motherboard, it doesnt support SAS. And yes, they are faster than SATA drives
posted by wongcorgi at 4:07 PM on July 10

SAS drives are faster, but are primarily used for the enterprise. Your motherboard doesn't support SAS (most, if not all, home PC motherboards don't). You're probably looking for a SATA drive intended for the PC enthusiast market, like the WD Velociraptor.
posted by strangecargo at 4:29 PM on July 10

Is my ASUS A8N32-SLI-Deluxe motherboard SAS harddrive ready?

No, you need an SAS card, which will easily eat your entire £100. £100 won't go far for a SAS HD either. The ones we get, 73GB 15kRPM Savvio's, cost about £250 a pop.

What in particular do you mean by "speed"? Is capacity a concern? Sequential transfer rate? Seek time? Reads? Writes? Concurrent access? How much beyond £100 would you go?
posted by Freaky at 4:38 PM on July 10

The increased speed isn't really noticeable doing desktop operations, other than the increased rotational speed that tends to come along with such drives. You're better off buying multiple SATA drives and using them in a high performance configuration (like RAID10 and separate spindles for OS/data, although even that's overkill and not going to get you much).

Get a 300GB VelociRaptor or two @$300US ea.
posted by kcm at 5:35 PM on July 10

You could spend $200 for a Samsung SSD. Those have some interesting potential.
posted by krisak at 7:48 PM on July 10

If you have slide-in SATA mounts, where you just push the drive in and it works (without manually connecting any cables), be aware that the Velociraptor doesn't have the connectors in the right locations for this to work.

Otherwise, it's the fastest thing spinning today. A bit out of your price range, but if you can stretch, it'll be worth it.
posted by kindall at 9:19 PM on July 10

FWIW, SCSI still reigns king as the fastest hard drives. They are $$$ and you could be shelling out $300+ just for the controller card.
posted by wongcorgi at 10:44 PM on July 10

Strictly speaking, the fastest hard drive you could get would be one of these, according to Toms Hardware. 4 in raid 0 absolutely destroy any previous notion of performance, even against 15k SAS drives. But, of course, they cost around $1000 USD a piece, so it's completely impractical, even for (most) enterprise shops.
posted by tracert at 11:37 PM on July 10

SAS is faster than SCSI according to the specifications. Whether the underlying drive can support that transfer rate is a different story.

Also, an important issue is how the adapter is connected to the computer- maybe this is less of an issue now, but I have a motherboard that has regular SATA connectors and an onboard RAID controller. However, the regular SATA controller is interconnected in a faster manner than the RAID chip, so the "faster" RAID is actually slower.

So if you jam a million dollar SAS controller into a PCI slot, it could be effectively slower than an onboard vanilla SATA...
posted by gjc at 7:32 AM on July 11

SCSI still reigns king as the fastest hard drives

SAS *is* SCSI, just.. er, attached serially, like SATA is ATA, attached serially.

Whether the underlying drive can support that transfer rate is a different story.

Drive, singular? Pfft, our main SAS disk shelves (can) connect 25 disks up via a single 4x SAS connector, and can be daisy chained; they could use 6Gbps per channel right now.

Also, even SATA can use breakout cables which connect up to 5 devices on a single connector. Plenty of room for using more bandwidth.

If sequential transfer rate is what you want; e.g. you're handling large media files and not doing quite so much seeking, a 1TB drive (or smaller one with similarly dense platters) will easily push 100MB/s near the outer edges, and Seagate 7200.11/ES2's have *very* good NCQ firmware if you care for multiuser/concurrent access. They also just hit £100, so have the benefit of actually fitting in your budget.

If seeks are the concern, VelociRaptors are about as good as it gets SATA wise, and probably the most you'd want to put in a desktop. A 15kRPM 2.5" Savvio is probably going to be faster, but you'll pay for it both in capacity and price, and you'll want a PCIe SAS card to go with it.

If seeks are a real concern, but you don't mind potentially quite slow random writes, a SSD might be in order; they excel at random reads, but tend to have poorer sequential access rates, and do very poorly at random writes. You also won't get much capacity for £100, maybe 8GB.

Also, you can reduce your need for good IO by getting more memory so the OS can cache more; I've seen some impressive numbers showing (uncached) load time in some games decreasing massively when going from 2GB to 4GB. Crucial are currently having a sale, so it's a good time to buy.
posted by Freaky at 9:47 AM on July 11