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Clabur
12-20-2000, 09:25 AM
Hi!
I'm thinking of buying a Initio Miles2 or the ATTO UL3D card. To the card I'd connect two Seagate Cheetah U160 or Quantum 10k II U160 disks, and stripe them with RAID 0.
My computer is a beige G3 desktop/upgraded with Newertech MAXpowr G4/400 card.
Alternatively I'd buy just the Miles2 and one disk, depending on how big the difference in transfer amount is. From what I understand, I can get about 40Mb/s in Sustained reads with just one disk and the Miles2.
Will it be any difference to mention with buying another disk and stripe it
with the first one in my G3-system? How many Mb/s?
In that case, will there be any difference to speak of if I buy the ATTO UL3D instaed of the Miles2 to the to striped U160 disks in my system? How many Mb/s?
Or should I just settle with one disk and a Initio Miles2card?
Since I use my Mac for audio recording it's quite important with a high transfer capacity.

Best regards
Clas P.

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jorge
12-20-2000, 11:06 AM
Clabur,

I run dual Cheetahs with an Initio Miles 2 in a Beige G3 running FileMaker Pro server in a raid 1. Disk Access increased 10 fold.

As for throughput, a single x15 on a Miles2 or Atto UL3 will give you 40 MB reads and 40 MB writes. Stripping two x15 will yield ~75MB reads and 40 Mb write on a Miles2 (maxes out at 40 Mb write). On the Atto board, about 75 MB reads and 55 to 60 Mb write.

Any single Cheetah with a Miles2 card will be enough bandwith for audio applications.

j

Clabur
12-20-2000, 12:02 PM
Hi Jorge and thanks for your reply!
What you write sounds very good. A transfer of ~75Mb/s with dual drives and the Miles2 is great, especially since the Miles2 is much cheaper than the Atto UL3D card. That the write speed maxes out at 40Mb/s isn't that crucial for me, it's more important with the read speed, because of the many audio tracks I use during playback.
Are the connectors on the Miles2 and U160 disks the same?
Can I connect the U160 disks directly to the Miles2 card or do I need a SCSI adapter (since the Miles2 is a UW2card)?
From what I understand the Miles2 has one internal and one external connector.
Do I have to lead a cable from the external connector into the computer, or how do I connect the two disks?
A lot of questions but I appreciate your advice on this.

Best regards
Clas P.

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magician
12-20-2000, 05:15 PM
both ATTO UL3D and Miles2 have 68-pin MicroD connectors internally. Externally, the ATTO, being a dual-channel card, uses the smaller .8mm Champ connector, two of them, on the backplane. The Miles2 uses the standard external 68-pin MicroD, since it is a single-channel card.

the Miles2 includes cabling and termination. The ATTO does not. You must purchase cables and terminators separately, adding further to its cost.

in a beige G3, Miles2 performs well. If you do not plan, at some future point, to migrate from the beige machine to a new Power Mac, I would consider the ATTO a relatively hard sell. Remember, it is a 64-bit card, and the beige G3 is still a 32-bit machine.

I should also mention that we still have remaining inventories of the Apple/Adaptec 2940U2B on our liquidations page, including a $100 bundle with cable, card and termination. Not the fastest card, but a steal at the price.

kaye
12-20-2000, 05:17 PM
Clabur,

Miles2 is a kit, meaning Miles2 (U2W) and Initio twisted-pair LVD internal cable and Initio LVD terminator and SoftRAID. The end of the cable plugs directly onto the Miles2 internal connector and then plugs directly into your first U160 LVD X15, then plugs directly into your second X15, and the LVD terminator is already plugged onto the end of the cable. You can forget the external connector. And you do not need any adaptors to do this. You will love those X15's. k

Clabur
12-20-2000, 05:44 PM
Ok that sounds good http://macgurus.com/infopop/emoticons/icon_smile.gifI'm thinking of installing the two disks in the two free
3,5" bays in my Desktop. I also thought of removing the frontplate which covers the lower bay and switch it to a plate for Zip or Jazdrives. Then install two fans inside the Zip or Jaz plate so that fresh air comes into the computer case. Do you think that will be ok, regarding the temperature in the computer? I've read that it's not recommended to stack two high-rpm disks on each other but obviously it will be the easiest and most convenient way in my case.
The disks I probably will buy are two Cheetah 18XL 9.2 Gb ST39204LW.(the X15's are a bit expensive for me right now)
What do you think is the best solution here?


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kaye
12-20-2000, 06:19 PM
Clabur,

Never touched a Beige G3, so I will have to defer to someone else on the subject of drive location and cooling. The ST39204LW is an excellent drive. I have three of them in various computers. However the X15, just one of them, is the equivalent in speed of between two and three of those ST39204LW drives in striped RAID and total size will be the same, 18GB since you are planning on two, with less hassle. I would opt for the X15 myself, but one X15 will eventually make you yearn for two. But either choice would really go. k

Clabur
12-20-2000, 06:48 PM
Is that right? That one X15 is about the same speed as two or three striped ST39204LW? I thought it was possible to get a sustained read of about 75Mb/s with two ST39204LW. Isn't a single X15 about 40Mb/s in sustained read?


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jorge
12-20-2000, 07:56 PM
Clabur,

the 75MB a sec read off dual disks is only attainable with dual x15s. The dual 9Gb Cheetahs will yield closer to 55 MB a sec.

The x15s are kick ass.

j

Clabur
12-21-2000, 04:21 AM
I see. Well, maybe I should settle with just one X15 for now, instead of two striped ST39204LW. That way I don't have to worry about if having two highspeed disks stacked inside my G3, will be too hot. I can install the X15 in the G3 desktop's lower 3,5" bay and that way have plenty of space above the X15 since the upper 3,5 will be empty. And maybe even add some sort of fan, at the front of the disk like the idea I wrote about earlier or maybe Macgurus UltraThin Heat Exhauster?

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magician
12-21-2000, 05:04 AM
we've discussed fan placement inside the G3 DT case before on these forums. It's the same as the 7300/7500/7600-style case.

if you look at the steel chassis directly behind the lower drive bay, you will see the fan mounting station. There are predrilled screw holes and ventilation holes there. The easiest way to mount a fan there is to make a pencil rubbing of the area and take it to your local hardware store. Little PC stores in strip malls are good sources.

make sure that the fan you get is deep and beefy, with a drive Molex power connector pass-thru so you can easily power it. Don't forget to get long screws and bolts so you are ready when you get home.

fans of this type will generally have markings on them depicting the direction of fan rotation and air-flow. You want to orient the fan on the chassis so air flows from left-to-right as you face the front of the machine. This will accelerate air-flow inside the chassis, venting hot air out the rear thru the power supply.

no other means of cooling this case design have come to light, though we have mounted fans on the far-left side of the chassis inside the machine, to the left of the PCI slots, in some cases. This was sort of a hack, and ended up being over-kill.

X15's run surprisingly cool. They do not require special cooling.

Santilli
12-21-2000, 06:41 AM
Hi
Not mentioned here is that 75MBsec is tops for the G3, due to the grackle chip not allowing any higher transfer rates. I have 4 x15's and an ATTO u3 card, and only get 70/75MB sec. Only the writes get faster, reads are limited at 75.

The advantage of the ATTO card is it is capable of 180 MB a sec on a 64 bit, 66 mhz pci bus. So, if you buy a new machine, you might want to buy now, or later to take advantage of the faster bus speeds.
On the otherhand, by the time you buy a new machine, the ATTO card might have competition, and be cheaper.
The miles is probably the most cost efficent, and it's easier to cable.

Somewhere we found a sled that mounted on the floor of a beige desktop, and mounted a couple 9 gig UW cheetahs in it. Quick access times, it seemed, and about 25-28 MB sec for raid 0.

I thought, and still think, it was really snappy.
I used one of the standard bays, and the one on the floor, and pulled the ide drive. Depending on version, your beige may not boot from the raid with the ide drive in place.

Two x 15's in Raid 0 would be as fast as this machine is capable of. The X 15's are THAT good, and you might try one first. Try that as a boot disk, and if that doesn't ring your bell, add another, and you will know that's as fast as your beige can go, at least for reads.

gs

Clabur
12-21-2000, 07:03 AM
Thanks for your answers everybody, they help me a lot in my decision of what to buy. I think I will start with one X15 and the Miles2.
What software do I format the drive with?
Can I use Softraid, which is bundled with the Miles2, even when it's just one disk I use. Or should Softraid only be used when striping two or more disks?

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kaye
12-21-2000, 09:50 AM
CP,

Despite its name, SoftRAID can be used on a single hard drive and is the fastest driver I know of. You just can't use it on a removable. k

magician
12-21-2000, 03:15 PM
right.

make sure you remember to update firmware on the Miles2 to 1.06b and SoftRAID to revision 2.2.2. Updates are on our FTP site, and at www.initio.com (http://www.initio.com) and www.softraid.com. (http://www.softraid.com.)

also remember that you may need a drive sled, depending on which bay you plan to use. The top bay to the left of the floppy in the beige G3 DT uses part number K8030. The lower bay to the left of the CD-ROM uses part number 922-1124. Both are on our parts page (http://www.macgurus.com/shoppingcart/obj_show_page.cgi?mgscsibezelsandsleds.html).

[This message has been edited by magician (edited 21 December 2000).]