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Upgrade or NEW install
- Thread starter BigDave
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They have a 4 pin power plug. If you look at the items for sale you will see a small connector on the module and then frequently you will see the power connector in the add, but not always. The only thing I like about a DOM is it doesn't eat up a drive location. The downside might be availability and physical spacing of SATA connectors on a MB.
jgreco
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In addition to the previous response by joeschmuck I will note that mainboards sometimes offer a SATA DOM power header so you don't have to jerry-rig a solution - especially important in a prebuilt whitebox server like a Supermicro.
BigDave
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So why not choose a 10 pin usb version if you have say X9SCM with a 10 pin socket already onboard.
The power would be directly to the DOM via the usb 5volts, no jerry-rigging required.
Perhaps a new thread for Disk On Module (future uses for embedded systems) is warranted...
The power would be directly to the DOM via the usb 5volts, no jerry-rigging required.
Perhaps a new thread for Disk On Module (future uses for embedded systems) is warranted...
The main problem with USB is the lack of long-term reliability when handling large numbers of writes and such. There is limited power available for USB and so the memory controller is very rudimentary. It's just enough to get the job done and not much more.
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I agree with this comment if you are talking about a Flash drive where it's memory type does not handle a large amount of writes compared to other media such as a SSD. Homework should be done on the devices to figure out the type of memory they use and expected number of erase/writes a cell can handle before failure.
I do not agree with this comment. If a USB port can power up an external USB hard drive using 4 pins (2 for power and 2 for data) then it should be able to power any other USB made component.
This is a good idea because there will be other folks asking for details and "what is the best one to purchase" type questions.
Sorry, let me correct myself. The USB has limited size (not power) because people don't want to haul around an oversized USB stick. Many USB sticks have very poor failover to the spare space (often it causes more problems than its worth when a location fails)
The problem isn't directly because of erase cycles, the problem is they don't have features like wear leveling, etc. so as soon as you start wearing out a particular location things go downhill pretty fast.
I've already got some rudimentary stuff in the works for DOMs. I got 2 different models I'm testing right now. ;)
The problem isn't directly because of erase cycles, the problem is they don't have features like wear leveling, etc. so as soon as you start wearing out a particular location things go downhill pretty fast.
I've already got some rudimentary stuff in the works for DOMs. I got 2 different models I'm testing right now. ;)
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Damn, I can't argue your last posting. ;) I would love to see the throughput benchmarks on those devices.
So I think the argument for or against DOM will be cost and longevity, not really connectivity. Here is how I see it...
Connectivity: If a user has an available SATA port then that is the best place to invest into a storage product. If they do not then a USB adapter of sorts would be the next best thing.
Longevity: What features does a DOM bring that a typical SSD doesn't have, besides possibly a smaller form factor and no mounting required?
Cost: A 16GB DOM is approximately $36 to $60 (according to my quick Google Shopping search). The cost of a new 64GB Internal SSD is $40.
Also I'm curious on the technology built into a DOM, I'm sure there are different qualities/speed of Flash memory being used.
@BigDave, see what can of worms you opened up! :p
So I think the argument for or against DOM will be cost and longevity, not really connectivity. Here is how I see it...
Connectivity: If a user has an available SATA port then that is the best place to invest into a storage product. If they do not then a USB adapter of sorts would be the next best thing.
Longevity: What features does a DOM bring that a typical SSD doesn't have, besides possibly a smaller form factor and no mounting required?
Cost: A 16GB DOM is approximately $36 to $60 (according to my quick Google Shopping search). The cost of a new 64GB Internal SSD is $40.
Also I'm curious on the technology built into a DOM, I'm sure there are different qualities/speed of Flash memory being used.
@BigDave, see what can of worms you opened up! :p
Both of mine do over 100MB/sec. The reality is that you don't really need a high throughput for the boot device.
I do have some comments regarding the DOM, SSD, etc discussion, but I'll keep my comments out of public places... for now.
I do have some comments regarding the DOM, SSD, etc discussion, but I'll keep my comments out of public places... for now.
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Over 100MB/sec is good. Well I'm sure we will have this DOM discussion soon and I for one can't wait since it would be new to me.
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