[Eriamjh]

Does anyone know if the serial ATA drives in the new G5s are going to be TRUE serial ATA drives or merely old fashioned parallel ATA drives that have been converted to serial ATA via an onboard P-ATA to S-ATA converter chip.

I ask because converted P-ATA drives don't really have any more performance than the old P-ATA drives and if Apple has not chosen a true S-ATA drive, we won't see a big disk performance boost.

Does anyone know the model number or brand of S-ATA drives being used or is it still too early to ask?

[Link]

oh they're true SATA drives. Don't worry about that.

[Hydra]

It looks like the 250 GB models that are optional may be the new Western Digital 250GB SATA WD2500JD. NewEgg has them for about $340. Theses are the only 250's I can find so I think that this may be the model. The smaller drives could be any number of mfg.s. It looks like for once Apple is charging a fair price for their HD upgrades - the bump from the 160GB to the 250GB costs $125.

-Jerry C

[Animu$]

Originally posted by Eriamjh:
Does anyone know if the serial ATA drives in the new G5s are going to be TRUE serial ATA drives or merely old fashioned parallel ATA drives that have been converted to serial ATA via an onboard P-ATA to S-ATA converter chip.

I ask because converted P-ATA drives don't really have any more performance than the old P-ATA drives and if Apple has not chosen a true S-ATA drive, we won't see a big disk performance boost.

Does anyone know the model number or brand of S-ATA drives being used or is it still too early to ask?

you still wont see a big performance boost only a mild one. Drives are still too slow to max out even the ATA100 bus. the only drive out now that does more then a mild boost in performance is the Western Digital SATA 10,000RPM and 5.2ms seek time drives.

[Commodus]

They're real Serial ATA drives.

For the most part, the claims regarding speed are correct. Hard drives are actually influenced more by their RPM rate and cache size than the speed of the ATA controller. It would be better to have a 10000 RPM ATA133 drive than a 7200 RPM Serial ATA drive. Likewise, an ATA133 drive with an 8 MB cache will outperform a Serial ATA drive at the same speed with a 2 MB cache.

That's not to say that you won't ever see a performance boost with Serial ATA, but at the moment it will probably be under very specific conditions: namely, instances where two hard drives are active and under a heavy load. Serial ATA requires that each hard disk be on its own channel (hence serial), so each drive gets as much bandwidth as it wants.

[CIA]

Apparently the 10,000RPM drives are not as fast all around as we thought.
http://www.extremetech.com/article2/...1184131,00.asp

[Eriamjh]

So the only real benefits are the separate busses and the "potential" for faster drives in the future that exceed current drive performance.

I guess Apple wanted to cool the HDs for the potential of hotter drives, hence the CD-ROM/HD cooling area.

As usual, I have to wait for benchmarks.

[Link]

If you want real speed go get a U320 drive that works at 3.4ms rate.

They're also godly expensive.. but about 3x faster then normal drives :drool:

[TheMosco]

Aren't sata drives hot swappable?

[rambo47]

I read somewhere that 500 GB SATA drives are on the way. Toshiba I think. I can't wait to have a terabyte of storage!

[CatOne]

Originally posted by TheMosco:
Aren't sata drives hot swappable?

Certainly not internal ones!

The swappability of the drives really depends on the enclosure. Standard IDE drives can be made "hot swappable" -- for example the drives Apple currently uses on Xserve and Xserve RAID are IDE drives and they're hot swappable. But they're mounted in Apple Drive Modules which take care of the hard work.

[Commodus]

Serial ATA was designed with hot-swap ability in mind, but you may not be able to do it on current G5s. You know that transparent plastic wall on the inside of the case that helps with airflow? It's technically required for the machine to boot, at least when the main metal door is off. Unless there's a hole in the plastic wall around the secondary drive bay, you'll probably need to have the system off for a swap.

[Hydra]

Originally posted by Commodus:
Serial ATA was designed with hot-swap ability in mind, but you may not be able to do it on current G5s. You know that transparent plastic wall on the inside of the case that helps with airflow? It's technically required for the machine to boot, at least when the main metal door is off. Unless there's a hole in the plastic wall around the secondary drive bay, you'll probably need to have the system off for a swap.

Yeah but interestingly that plastic internal cover does not cover the drive bays at the top - the optical and HD section at the very top of the case is always exposed with the metal door off. I was wondering about the hot-swappable nature of the SATA drives too but from what I have come across many first generation SATA devices may not really support this feature.

-Jerry C

[tooki]

Originally posted by Commodus:
...Serial ATA requires that each hard disk be on its own channel (hence serial), so each drive gets as much bandwidth as it wants.

No, they're called "serial" ATA because they transmit data in a serial fashion -- one bit after another over just one data path. Parallel ATA transmit data in parallel: 8 bits are sent over 8 data paths, at the same time.

It has nothing to do with how many drives can be connected to one controller.

SCSI is also parallel. (Although serial SCSI is on the way, too.)

FireWire and USB are serial, as is ADB and, of course, the venerable serial port (which is in fact an RS-232 port on PCs, ora fancy RS-422/RS-232 switchable port on a Mac).

What you are confusing is series vs. parallel (which is an electronics term), with serial vs. parallel (which is computing terminology). In computing, how the devices are physically arranged on a bus is referred to as the "topology": daisy-chained (like LocalTalk, SCSI and FireWire, where one gadget can be connected off of another gadget), as opposed to a star or tree topology (where something, like a hub or computer) acts as the central point, to which everything is attached directly (hubs being the only possible thing inbetween a gadget and the central point). USB and Ethernet are examples of this. Serial ATA is a super-simple tree topology: the computer is the central point, and the drive is the device. Parallel ATA is also a tree: both drives on one bus are connected directly to the computer. (For it to be daisy-chained, the drives would need to have two connectors on them, which they clearly don't.)

tooki

[tafticus]

Is the new ATA bus still backward compatible with older ATA drives? If so, would having one on the 2nd channel hurt performace of the primary drive?

[Hydra]

Originally posted by tafticus:
Is the new ATA bus still backward compatible with older ATA drives? If so, would having one on the 2nd channel hurt performace of the primary drive?

No, the data and power cables are different. A PATA to SATA adapter card (around $25) is necessary to use an older PATA drive with the newer SATA. I have no info about using 2 drives on the one adapter hooked into the onboard SATA - if that is what you are asking.

SATA only allows for one drive per controller so you never run into master/slave jumper mumbo jumbo stuff and the subsequent performance hit from having the 2 drives share the same channel and bandwidth. I think this was mentioned a bit above.

Here is a link to some info and pictures comparing old and new...

http://www.directron.com/patasata.html


-Jerry C

[OreoCookie]

Look at what Tooki said.
The converters simply convert electrical signals. The first serial ATA drives had such a converter built-in as they were standard ATA drives (parallel) connectors with said converter.