Serial ATA

[wsteineker]

Ok all you hardware wizards out there, here's one for you. What do you think of Serial ATA? Is it worth the investment at this juncture, or should I just stick with my ATA 66/100 drives for now. It seems to be a bit less expensive than SCSI, but at comparable speeds. Are there any OS X compatible controller cards? Thanks for your input.

 

[TyleRomeo]

Re: Serial ATA

Originally posted by wsteineker
Ok all you hardware wizards out there, here's one for you. What do you think of Serial ATA? Is it worth the investment at this juncture, or should I just stick with my ATA 66/100 drives for now. It seems to be a bit less expensive than SCSI, but at comparable speeds. Are there any OS X compatible controller cards? Thanks for your input.

S-ATA will take over soon, if you have a power mac (MDD) i suggest waiitng for it to come, cables are thin as hell and wont burn up your powermac, look for sonnet to come out with another trio card for this macworld. I see a USB 2.0, Firewire 800 and s-ata controller in the works come july.

Tyler

 

[melchior]

S-ATA is very cool and coming fast. i would however hold off for now. probably another year, but maybe sooner. unless you were about to buy a fat scsi drive in which case a S-ATA controller could be seen as future thinking, otherwise hold off. your cheque-book will thank you.

 

[madamimadam]

From what I have seen in real world tests (instead of those lovely theoretic peaks), serial ATA drives are still performing slower than parallel ATA drives.

 

[hvfsl]

Originally posted by madamimadam
From what I have seen in real world tests (instead of those lovely theoretic peaks), serial ATA drives are still performing slower than parallel ATA drives.

That is true, but only because they are basically the old parallel drives with S-ATA connectors on them. Also most S-ATA controllers are not fast enough to take advantage of the speeds of S-ATA. Hyper Transport in upcoming Macs will solve this speed issue, but only on drives that are not just parallel ATA drives with S-ATA connectors. Also you will see no advantage using a S-ATA PCI card since these will be slower than using normal inbuilt Parrallel. The only way to take advantage of S-ATA is in the new Hyper Transport Macs (whether they will have a PPC970 still remains to be seen).

S-ATA speeds will only become aparent in the PC world when AMD and Intel start using Hyper Transport which they plan to do in late 2003, earily 2004.

 

[iJon]

hell, i just like sata because it looks cool and i dont have big fat cables in my computer, although i did switch to rounded cables in my pc, sata would still be better.

iJon

 

[solvs]

S-ATA is still new, and not that much faster. As others have noted, it can actually be slower when using the bastardized version so common at this point. As MB specs ramp up, so will S-ATA speeds. 300 - 600 MB/s and 10,000+ RPM speeds. Lower access times. Bigger capacity, bigger buffers. When we start reaching terabyte size drives, we need something faster than current ATA can handle.

SCSI is okay. Still fast (with lower access times and higher RPMs). And reliable. But expensive. There's also fibre-channel. Also fast, also expensive.

So yes, someday S-ATA may be the new standard. But it's not really worth it yet.

 

[pgwalsh]

Originally posted by solvs
S-ATA is still new, and not that much faster. As others have noted, it can actually be slower when using the bastardized version so common at this point. As MB specs ramp up, so will S-ATA speeds. 300 - 600 MB/s and 10,000+ RPM speeds. Lower access times. Bigger capacity, bigger buffers. When we start reaching terabyte size drives, we need something faster than current ATA can handle.

SCSI is okay. Still fast (with lower access times and higher RPMs). And reliable. But expensive. There's also fibre-channel. Also fast, also expensive.

So yes, someday S-ATA may be the new standard. But it's not really worth it yet.

Couldn't quite follow everything you were saying... but I think I agree with you.

The main factor that needs to take place is the RPM of the drives. It doesn't make sense to buy a serial ata drive if it's running at 7400 RPMs or slower. You wont notice that much of a difference. With drives in the 10,000 to 15,000 range you'll notice the difference and reap the benefits. S-ata drives are currently not raid compatible, but correct me if I'm wrong.

 

[yzedf]

higher rpm != higher speed drive

you can, in theory, locate the bits on the drive closer together, keep the same rotational speed, and end up with a faster drive. i think that is the pixie think IBM referred to recently (not the tv advert)...

http://www.research.ibm.com/resources/news/20010518_pixie_dust.shtml

(I guess 2001 is not so recent...)

also, 16MB cache would help (or even 24-32MB).

SATA drives and corresponding hardware (mobo, daughter cards, etc) will get better. Think rev A versus rev D for a Mac product.

 

[madamimadam]

Originally posted by solvs
SCSI is okay. Still fast (with lower access times and higher RPMs). And reliable. But expensive. There's also fibre-channel. Also fast, also expensive.

If I am not mistaken, Fibre-Channel is usually SCSI with a Fibre-Channel interface.

 

[madamimadam]

Originally posted by yzedf
higher rpm != higher speed drive

Just what I was going to say... you would NOT see any extra benifit going to S-ATA because you are using a 10000+ RPM drive.

Drives are read at the speed of a 5400RPM drive. The reason 7200RPM is faster is because you are making sure there is data ready to be read in the more than common situations where every bit of data you want to read is in perfectly in line from start to end of drive and also it is very common for the drive to miss data and have to read it on the next rotation.

Even if the data could be transfered faster than it is, 10000RPM would never be almost double the speed of 5400RPM because, while those drives keep the data "queue" full, they miss the data a lot more often.

The real benifit of Serial ATA is in the reduction of bottlenecks with multiple drives and line interferance (can't remember the correct term for this).... at least for the moment... this will change with time but I would not be surprised if the upcoming faster Serial ATA standards get delayed due to a lack of devices fast enough for it.

 

[madamimadam]

Originally posted by iJon
hell, i just like sata because it looks cool and i dont have big fat cables in my computer, although i did switch to rounded cables in my pc, sata would still be better.

iJon

Only thing is, while the cables are smaller, there is also more of them since you need one per device.

 

[DeepIn2U]

Great things to come

SATA drives should promise higher efficient use of bandwidth to the drive. I've only seen info up to 500MB/s, and currently only 150MB/s is available from Seagate (7200RPM), and now Western Digital 360GD has a 10'000RPM drive with 6.8ms seek time! Even if a comparable ATA/100 and a SATA/150 drives both have 4200RPMs for say a laptop, I'd prefer the later.

Agreed there is no sense to have a PCI slot inside of your mac to support it just yet. I'm hoping Apple isnt foolish enough to leave it out of the next X-Serve or even the PowerMac line, since both are serious Server contenders which would benefit immensely with SATA drive seek times, data transfer times, and sheer reliability; especially if your using a database!