Recommend me a Power Suppy for 9 SCSI 10k RPM Hard Drives

Status
Not open for further replies.
R

Rob Black

2[H]4U
Joined
Mar 11, 2005
Messages
2,282
Hi :D

So I am in the process of building my “super pc”. So far I have 9 Atlas 146GB 10k SCSI drives, and I also plan to have 2 – 3 Sata Drives. All this is going to be enclosed in the new Stacker 830 case. What kind of power supply will I need to power all this stuff? Will something like this be strong enough?

http://www.newegg.com/Product/Product.asp?Item=N82E16817703005


Or will I have to buy a 1KW power supply?


Thanks alot
;)
 
Figuring 30 watts per drive to account for the startup surge is a pretty safe bet. So a 375 watt would power the drives, but if this will be a whole system, or you plan on adding drives in the future adjust accordingly.
 
Does the SCSI controller have staggered booting? If so, you shouldn't require that much...since I doubt you'll ever have all 9 HDs running at full throttle.

How come you didn't go for the SAS 15k Cheetahs? :p
 
HDD's use about +12V@3A each, in addition to some +5V.

When dealing with a large number of HDD's, I always recommend a PSU with one very strong +12V rail,
so your suggestion of the PC P&C 610W with +12V@49A is ideal.

Good Luck,
Dave ;)
 
davidhammock200 said:
HDD's use about +12V@3A each, in addition to some +5V.

When dealing with a large number of HDD's, I always recommend a PSU with one very strong +12V rail,
so your suggestion of the PC P&C 610W with +12V@49A is ideal.

Good Luck,
Dave ;)
Click to expand...
What hard drives are you dealing with? All the ones I'm familiar fall in around 25W... at spinup. I usually budget 1A/1A running and 2A/1A at startup for hard drives.

Edit: The Raptor, for example, only takes 10 watts read/write. That's less than an amp.

OP, I have run 13 hard drives, a dual p3, 2 gigs of ram, and 2 sata controllers on this. What other hardware is going in this system?

Last, Cheetahs aren't exactly the epitome of speedy. At least recommend him Fujitsu MAXes; they're a good deal faster and a few bucks cheaper too IIRC.
 
unhappy_mage said:
What hard drives are you dealing with? All the ones I'm familiar fall in around 25W... at spinup. I usually budget 1A/1A running and 2A/1A at startup for hard drives.

OP, I have run 13 hard drives, a dual p3, 2 gigs of ram, and 2 sata controllers on this. What other hardware is going in this system?

Last, Cheetahs aren't exactly the epitome of speedy. At least recommend him Fujitsu MAXes; they're a good deal faster and a few bucks cheaper too IIRC.
Click to expand...
That is what it says on Seagate's website. ;)
 
Yup, that 610 is what you want. Nothing else has near that amount of 12v amperage on a single rail. Now if you were in Asia, and you had access to a Seventeam st-620, you would not be dissapointed either.. 18a on rail1, and 32a on rail2. 30 on the +5 and 25 on the +3.3 too.

Sadly, it's not available here.
 
unhappy_mage said:
What hard drives are you dealing with? All the ones I'm familiar fall in around 25W... at spinup. I usually budget 1A/1A running and 2A/1A at startup for hard drives.

Edit: The Raptor, for example, only takes 10 watts read/write. That's less than an amp.

OP, I have run 13 hard drives, a dual p3, 2 gigs of ram, and 2 sata controllers on this. What other hardware is going in this system?

Last, Cheetahs aren't exactly the epitome of speedy. At least recommend him Fujitsu MAXes; they're a good deal faster and a few bucks cheaper too IIRC.
Click to expand...

Are the 15k.5 Cheetahs not faster? I couldn't find a review..but I coulda sworn I saw one earlier. :p
 
davidhammock200 said:
That is nice, however they will pull up to +12V@3A at "spin up". :rolleyes:
Click to expand...
Thanks for posting a link to seagate. I'm up to three links, two manufacturers, none of which show more than 20W at any time. Oh, and Atlas 10k's are made by Maxtor not Seagate. They may have been bought out, but there's still no docs for them on Seagate. Maybe we could have a relevant discussion, or maybe you could keep talking about the wrong drive.

Lastly: my god, you're arrogant. I see why JonnyGURU left. Making statements without proof, and then when I post contradictory information, what do I get? Same assertion, and a :rolleyes: for my trouble. If you'd point out what your source is, I'd appreciate it. That is all.

 
unhappy_mage said:
Thanks for posting a link to seagate. I'm up to three links, two manufacturers, none of which show more than 20W at any time. Oh, and Atlas 10k's are made by Maxtor not Seagate. They may have been bought out, but there's still no docs for them on Seagate. Maybe we could have a relevant discussion, or maybe you could keep talking about the wrong drive.

Lastly: my god, you're arrogant. I see why JonnyGURU left. Making statements without proof, and then when I post contradictory information, what do I get? Same assertion, and a :rolleyes: for my trouble. If you'd point out what your source is, I'd appreciate it. That is all.

Click to expand...
Seagate has rearranged their site since I last posted this type of information. I do not have the time to "dig it out" for you.
Believe whatever you wish, but you had better allow +12V@3A for each HDD at "start up" or you will wish that you had, unless you are using a staggered start up.

I have only been configuring servers since 1979, so what do I know. :rolleyes:
 
Appeal to authority, eh? Nice.

Oh, and by the way, OP, Maxtor (see page 54) specifies their draw at startup at less than 20 watts. Even the power supply I linked above was handling more than enough to run 9 of those just fine.

Meanwhile, I've had it with this thread. I'll weigh in if you mention the rest of your hardware, but until then adieu.

 
aznx said:
Does the SCSI controller have staggered booting? If so, you shouldn't require that much...since I doubt you'll ever have all 9 HDs running at full throttle.

How come you didn't go for the SAS 15k Cheetahs? :p
Click to expand...

This is the card I am going to use

http://www.lsilogic.com/products/megaraid/megaraid_320_2e.html

I was also looking into getting 3 of these

http://www.scsi4me.com/product_info.php?cPath=4_12&products_id=917

or should I just get some 80pin to 68pin Converters?

Is there any real benefits to using the cages? Will I still need a Terminator if I use the cages?


Thanks guys for all the info.
 
unhappy_mage said:
Appeal to authority, eh? Nice.

Oh, and by the way, OP, Maxtor (see page 54) specifies their draw at startup at less than 20 watts. Even the power supply I linked above was handling more than enough to run 9 of those just fine.

Meanwhile, I've had it with this thread. I'll weigh in if you mention the rest of your hardware, but until then adieu.

Click to expand...
HDD +12V current used at spin-up:

Electrical Requirements

Current

Typical Current (12VDC +/- 5%) 0.433 amps
Startup Current (12VDC +/- 5%) 2.8 amps
Typical Current (5VDC +/- 5%) 0.401 amps
Startup Current (5VDC +/- 5%) 0.841 amps
Power

Seek Power (typ) 12.4 watts
Read/Write Power (typ) 12.8 watts
Idle Power (typ) 7.2 watts

http://www.seagate.com/cda/products/discsales/enterprise/tech/0,1084,700,00.html
Click to expand...
See graph on page 31: https://searcheng.seagate.com/cs.html?charset=UTF-8&la=en&qt=+12v 3a&url=http://www.seagate.com/support/disc/manuals/scsi/8900b.pdf&col=www

See graph on page 38: https://searcheng.seagate.com/cs.html?charset=UTF-8&la=en&qt=+12v 3a&url=http://www.seagate.com/support/disc/manuals/scsi/cheetah_15k4_scsi_pm.pdf&col=www

See graph on page 40: https://searcheng.seagate.com/cs.html?charset=UTF-8&la=en&qt=+12v 3a&url=http://www.seagate.com/support/disc/manuals/fc/cheetah_15k4_fc_pm.pdf&col=www

I could quote hundereds more docs from many different HDD makers, but I hope you get the idea! :rolleyes:
 
454Casull said:
Do you also take into account the lower draw of other components at boot?
Click to expand...
In a server, what components draw very little power st start up?

AFAIK, only GPU's do this & servers do not use highend DPU's.
 
davidhammock200 said:
HDD +12V current used at spin-up:
Click to expand...
Your first link is for the NL35 series. 7200 RPM, up to 4 platters. Your other three don't work, but the 8900 manual specifies that the maximum DC required is 2.18A. Maximum AC exceeds that by a good bit (3.1A) but that's for a maximum of 5ms.
At power-up, the motor current regulator limits the 12V current to an average value of less than 2.0A, although instantaneous peaks may exceed this value. These peaks should measure 5 msec duration or less.
Click to expand...
BUT
that's not relevant, at all. The drives in question are neither Seagate, nor 7200 rpm, nor 15k rpm. They're Atlas 10k (V series linked, but it could be the IV based on the description).

Thus, the final word, unless you want to buy one and produce more accurate figures yourself, must be that they consume 1.33A@12V (Atlas V) or 2.2A@12V (Atlas IV) at startup. Both figures are 10ms peak values.

I'm not arguing about what the power supply should be specced at - but saying that the manufacturers require 3A across the board is simply false. I should drop the issue now, since it's fairly obvious I'm not making any headway here. Lastly, :rolleyes:
 
davidhammock200 said:
In a server, what components draw very little power st start up?

AFAIK, only GPU's do this & servers do not use highend DPU's.
Click to expand...
So I am in the process of building my “super pc”
Click to expand...
It's pretty safe to say he's got at least a 7900GT in there.
 
This thread is done. The OP's question has been answered. If not the OP can PM me for a reopen or start a new thread.

I will take the time now to say that certain members behavior of late during my absence was bordering inappropriate and I will be taking a nice long look at this issue. This is normally a nice corner of the forum but certain members have begun to throw their weight around and I will not have the section become a battle of personalities. I think most of us pride ourselves on this section being free of conflict and such that can be a hassle for the mods of other sections, at least I do.
 
Status
Not open for further replies.
Back
Top