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Phoenix32 · 10-15-2006, 11:04 AM

Well, sorta,

On the Seagate yes, it is 12V @ 1.083A average, but don't miss that AMPS PEAK right above that section with 12V @ 2.8A peak. That peak current is going to be for hard disk spin up.

On the WD, you got lost a little. They do not use an average, but give the Read/Write (close enough) as 12V @ .530A and do not give a peak (spin up) at all on that chart.

Here is the problem (some of which I mentioned before) with all of that. Different manufacturers rate different ways or show different specs so it can become confusing (as you just found out). Also, let's go back to that Seagate chart a moment, I want you to see something.

Notice on the Seagate charts that while they did rate the 80 GB and 160 GB drive a little lower than the others, all of the others are rated the same. And if you look at the 12V peak amps, you will see they all draw 2.8A. WTF is that? The 80 GB and 160 GB models have 1 platter and the 750 GB has 4 platters and they are trying to tell me they take the same current to spin up. So X mass takes the same amount of power to get moving as 4X mass. Yeah, uh huh, right. This is what I was talking about when I said they tend to rate drives from a family of drives by the highest one, but are not consistant about even that. You can be assured that it changes from 1 platter drives to 4 platter drives. You can also be assured, that just like the 80/160 changed in the average specs from the others, the 200/250/320 are different than the 400/500 and 750 due to different number of platters, both on average specs and in peak. Bottom line, hard drive specs are a rats nest.

So what's a guy to do? Well, several things, best guess, read reviews, or measure it.

For example, if I had to guess, I would say the Seagate 7200.10 models go somewhere around these specs

80/160 - 12V @ 0.71A average and 1.9A peak
200/250/320 - 12V @ 0.84A and 2.2A peak
400/500 - 12V @ 0.96A average and 2.5A peak
750 - 12V @ 1.083A average and 2.8 peak

THESE ARE GUESSES! But I bet somewhere near the right area at least. This also shows the Seagate drives do use a little more power than the Western Digital drives. This is also shown to be true in measurements in a Storage Review a while back comparing 250 Gb drives if you go here

http://www.storagereview.com/articles/200601/250_7.html

Now the reason I recommended perpendicular recording drives is because they use less platters, and thus less power. More bang for the watt sorta speak.

As for drive manufacturers, and I am SURE to get a lot of flak and disagreement here (and that's fine). I would not give you 2 cents for a Maxtor drive. Hitachi's are good drives, but can be a little picky sometimes and too expensive. Samsung has okay drives, but not something I would use when betters can be had for the same money (samsung is getting better over time though). My preferences have always been Western Digital and Seagate. Seagates tend to eat more power and thus run hotter, as well as be more expensive, nor do they last any longer than Western Digital drives. Thus, I have a tendancy to buy Western Digital drives. And for the record, these opinions are based on being in a repair facility where we replaced literaly thousands of hard disks and due to military classified info possibly being on them, had to store them in vaults for disposal done once a year. Over time, you get a feel for reliability and value. The Western Digital drives tended to be a little more reliable and a better value for the money, including the Seagates. The down side of the Western Digital's is they tend to be noisier also.

Now why do people around here always say Seagate? Well, the #1 biggest reason is the 5 year warranty. In a SNAP NAS server, it is normal for these units to run 24/7. Given this kind of use, a 5 year warranty is nice, if you actually keep the receipts and register the drives. You will also find when it comes to hard disks, it is like cars. Some people like fords and some people like chevys.

My advice, stick in a pair of 250/320 GB Seagate or Western Digital hard disks and call it good. Just know you are exceeding the power limits maybe a little and could be cutting the life of the power supply, especially if you turn it on and off a lot (spin up power remember).

10-15-2006, 11:04 AM	#15
Phoenix32 Thermophile Join Date: May 2006 Location: Yakima, WA Posts: 1,282	Re: SNAP 2200 HDD Sizes ? Well, sorta, On the Seagate yes, it is 12V @ 1.083A average, but don't miss that AMPS PEAK right above that section with 12V @ 2.8A peak. That peak current is going to be for hard disk spin up. On the WD, you got lost a little. They do not use an average, but give the Read/Write (close enough) as 12V @ .530A and do not give a peak (spin up) at all on that chart. Here is the problem (some of which I mentioned before) with all of that. Different manufacturers rate different ways or show different specs so it can become confusing (as you just found out). Also, let's go back to that Seagate chart a moment, I want you to see something. Notice on the Seagate charts that while they did rate the 80 GB and 160 GB drive a little lower than the others, all of the others are rated the same. And if you look at the 12V peak amps, you will see they all draw 2.8A. WTF is that? The 80 GB and 160 GB models have 1 platter and the 750 GB has 4 platters and they are trying to tell me they take the same current to spin up. So X mass takes the same amount of power to get moving as 4X mass. Yeah, uh huh, right. This is what I was talking about when I said they tend to rate drives from a family of drives by the highest one, but are not consistant about even that. You can be assured that it changes from 1 platter drives to 4 platter drives. You can also be assured, that just like the 80/160 changed in the average specs from the others, the 200/250/320 are different than the 400/500 and 750 due to different number of platters, both on average specs and in peak. Bottom line, hard drive specs are a rats nest. So what's a guy to do? Well, several things, best guess, read reviews, or measure it. For example, if I had to guess, I would say the Seagate 7200.10 models go somewhere around these specs 80/160 - 12V @ 0.71A average and 1.9A peak 200/250/320 - 12V @ 0.84A and 2.2A peak 400/500 - 12V @ 0.96A average and 2.5A peak 750 - 12V @ 1.083A average and 2.8 peak THESE ARE GUESSES! But I bet somewhere near the right area at least. This also shows the Seagate drives do use a little more power than the Western Digital drives. This is also shown to be true in measurements in a Storage Review a while back comparing 250 Gb drives if you go here http://www.storagereview.com/articles/200601/250_7.html Now the reason I recommended perpendicular recording drives is because they use less platters, and thus less power. More bang for the watt sorta speak. As for drive manufacturers, and I am SURE to get a lot of flak and disagreement here (and that's fine). I would not give you 2 cents for a Maxtor drive. Hitachi's are good drives, but can be a little picky sometimes and too expensive. Samsung has okay drives, but not something I would use when betters can be had for the same money (samsung is getting better over time though). My preferences have always been Western Digital and Seagate. Seagates tend to eat more power and thus run hotter, as well as be more expensive, nor do they last any longer than Western Digital drives. Thus, I have a tendancy to buy Western Digital drives. And for the record, these opinions are based on being in a repair facility where we replaced literaly thousands of hard disks and due to military classified info possibly being on them, had to store them in vaults for disposal done once a year. Over time, you get a feel for reliability and value. The Western Digital drives tended to be a little more reliable and a better value for the money, including the Seagates. The down side of the Western Digital's is they tend to be noisier also. Now why do people around here always say Seagate? Well, the #1 biggest reason is the 5 year warranty. In a SNAP NAS server, it is normal for these units to run 24/7. Given this kind of use, a 5 year warranty is nice, if you actually keep the receipts and register the drives. You will also find when it comes to hard disks, it is like cars. Some people like fords and some people like chevys. My advice, stick in a pair of 250/320 GB Seagate or Western Digital hard disks and call it good. Just know you are exceeding the power limits maybe a little and could be cutting the life of the power supply, especially if you turn it on and off a lot (spin up power remember).