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PowerMike G5
Nov 11, 2005, 09:16 PM
Hi,

It is my understanding that inserting a SATA 2 drive in a new G5 would only run at SATA 1 speeds. How would I get the G5 (Quad) to take full advantage of SATA 2 speeds. Would I need something like the HIGH POINT RocketRaid 2320?

http://www.highpoint-tech.com/USA/rr2320.htm

I'd like to use the drives internally ... thanks.

jsw
Nov 11, 2005, 09:23 PM
Well, if you can find a card that's Mac-compatible, then that's what you'd need - AFAIK, there's no other way to get a PMG5 to "see" the SATA II drives as anything better than plain ol' SATA drives.

That card you mentioned?
Drivers are available for all major operating systems, including Windows, Linux, FreeBSD. Apparently, OS X is not a "major operating system".... :rolleyes:

Sun Baked
Nov 11, 2005, 09:25 PM
It's probably not going to matter much, since the max. transfer speeds are only for the cache.

The drives will still be limited to the same sustained transfer speed when the cache runs out.

A bigger better cache tuned towards your specific use may be just as important as trying to maximize the cache's max transfer speeds.

>jsw

The RocketRaid 2320 says PCIExpress/PowerMac G5 on the front page...

www.highpoint-tech.com

simie
Nov 12, 2005, 03:33 AM
http://www.highpoint-tech.com/


OS X does have drivers for the RocketRaid 2320 - just go to the Mac menu at the top of the page to the right of Support.

!0.3x to 10.3.4 is supported

PowerMike G5
Nov 12, 2005, 07:45 AM
Thanks guys ...

So is getting this card to hookup my 2 500GB SATA 2 internal HDs not worth it then? Should I juts hook them up to the main board and use SATA 1 speeds? Or will there be a good enough speed increase if using this card to connect my HDs instead?

Thanks.

Bear
Nov 12, 2005, 08:04 AM
Thanks guys ...

So is getting this card to hookup my 2 500GB SATA 2 internal HDs not worth it then? Should I juts hook them up to the main board and use SATA 1 speeds? Or will there be a good enough speed increase if using this card to connect my HDs instead?

Thanks.Just use the internal controller.

For the Hitachi 7K500 drive, the maximum sustained data transfer rate from the disk is under 65MB/sec.

The Seagate 500GB Barracuda is 100 Mbytes/sec Max. External Transfer Rate and I expect the sustained rate is not much different than the Hitachi.

Neither drive really offers any benefit being on a SATA 2 controller.

Sun Baked
Nov 12, 2005, 08:36 AM
Thanks guys ...

So is getting this card to hookup my 2 500GB SATA 2 internal HDs not worth it then? Should I juts hook them up to the main board and use SATA 1 speeds? Or will there be a good enough speed increase if using this card to connect my HDs instead?

Thanks.Some of the caches are 16MB doesn't matter if you suck them dry with any speed of SATA or ATA, once you burn through the cache -- the drives are limited to their mechanical limits 50-100MB/s.

.1 sec, .2 sec, .3 sec, .4 sec or even a second under ATA or SATA -- once the cache is gone, most of the drives are the same speed, only the marketing, price, and controllers vary.

For transfers that fit in the cache, they are zippy -- after that they all crawl.

They market the bus, and force you to hunt for the max sustained tranfser.

---

Since virtual memory uses the HD as an extension of the memory space, the quickest way to improve performace is to reduce the need for using the VM engine.

Since 100MB/s is a far short of even a G4s measly 1GB/s sustain FSB speeds, and well short of the FSB and memory in the G5s.