Hazards of using USB 2.0 powered optical/hard drives??

I'm thinking about getting the Samsung SE-S084B USB 2.0 powered
DVD burner. I've read one mention that using these USB powered drives can damage the USB port as the USB standard and the ports are not designed to deliver as much current as these USB-powered devices draw.

Is this true? Has anyone had something go wrong with their notebook/netbook after using such a drive for long stretches over a long period of time (Say 6 hours a day, 5 days a week)?

 

I've NEVER had a problem over the past 8 years using USB powered HDDs... and I have had them powered on for days at a time. I have encountered issues with DVD drives if I try to write with only the USB cable connected (often these devices will pull off of 2 USB ports) but reading has never been a problem with only the data cable connected.

 

I have an Samsung SE-S084B and it works fine off one usb port on my acer notebook , but i only use it now and again , if i was using it a lot i would use two usb ports to power it, less chance of blowing one.

But if you are worried you could buy and external writer that can use an external power supply if you want , I had a buffalo brand one , but you have to buy the power supply separate, I think a charger from a Sony PSP would work and can be bought off ebay cheaply.

 

Been using a portable DVD burner on my netbook without issue and portable hard drives for years. On one of my previous laptops used the portable drive so much (in and out) the USB slot was beginning to wear out from the constant plugging/unplugging - but the power aspect never was an issue. Additionally, some USB devices will come with a dual plug cable - one for power, one for data.

 

I would say the same thing. use Y-type USB cables to reduce the power load on each ports.


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I'm not understanding the problem OP. Do you have some power plug deficiency? In any event, USB powered devices are inferior anyway.

 

I'm not understanding your comment. In what way would a USB powered device be inferior, and to what?

- Tim

 

yup, there's a possibility of blowing your motherboard if you are using an external DVD burner. to minimize this burn the disc the slowest speed as possible. In this way, the laser will just use small amount of power during burning. Reading disc will not be a problem.

 

That's a bunch of bull. If a USB port could not supply enough power the most that would happen are failed burns. That's why it's recommended that you burn at the slowest speed possible. Most external DVD drives these days only need one USB port to function correctly. Some even have little LED indicator lights to tell you if it's getting enough power or not (my HP 556s does). If not you would use the (hopefully) supplied Y cable to supply enough power.

 

I think as long as the dvd burner is specified to run off a single USB 2.0 port, there is no risk of damaging your usb port. There are still models of external usb dvd burners that do need extra power and thus come with those y-splitter usb cables. I bought my LG model specifically because it was designed to run off a single port.

 

OP was asking for the hazard and damaging the MB is one of the hazards. There's a possibility using an external usb powered DVD burner. but very remote for usb powered external HDD.

 

A simple option (at lead for dvd writers) is to get a proper, powered external dvd writer, or build it yourself by putting a dvd writer in a 5.25 enclosure. You can then choose the best dvd writer, and use it at full speed.

 

Any branded device designed for a USB port will not damage a USB port unless faulty. (I suppose you could get some "junk product" that will damage a USB port, but its generally not one of the large brands but a no name product)

Generally a USB port should also shut down if a device wants to draw more power - should, if it does is another question.

But I'd not worry about it at all - on that note - I've been running 2 2,5" drives of one USB port via an unpowered HUB - no problems.

 

Just because the plug fits doesn't mean it's safe to use. Ever have a hair dryer trip the circuit breaker? My laptop has 4 USB ports; so does that mean I can run devices at max from all four ports at the same time?

 

@ Krane

No, I just wanted confirmation that using these USB powered devices would in no way damage both my notebook and the devices connected to it. I was just told that there was a limit to how much a USB 2.0 port was capable of outputting (outputting *safely* I'm assuming).

@ Everyone who responded.

Many thanks for all the responses everyone. My worries are eased.

 

A device at spec only draws, at max, 500mA. However, it's possible for a device outside the spec to draw up to 1A. However, these are typically novelty items and never marked with the standard - mug chiller/warmers, fans, lights, vacuums, lava-glitter lamps. Drawing power outside the spec can potentially cause issues.

My suggestion would be the setup I use - Powered USB hubs connecting all devices rather than directly into the motherboard or combo board.

 

No, that's a fairytale, and there is no such possibility. USB specs, of course, do include provisions for devices drawing excess currents. Any USB hub that is designed according to spec will either actively limit the current, or turn itself off if a device attempts to draw too much current.

 

Ah, yes you can. This the whole point of USB power and power management. If a connected device is trying to pull more power than the port is designed to deliver, the *port* shuts off. No problem. Doesn't affect the other ports.

Individual 2.0 ports are current limited to 0.5 amps. v3 ports double that to 1.0 amps per port.

A poorly designed laptop might have problems. But if it does, it's working outside of the specification for USB hubs and ports.

 

Sorry for the late reply. I was simply stating that there is no chance that it will "fry" the motherboard. At worst the component will simply refuse to function.
I was just a bit irritated because some times people come here and spread misinformation (they simply don't know what they are talking about) and I felt this was something I had to set straight.
There is no danger or hazard in running something that might try to draw too much power from the USB port. They are only designed to output a certain amount of power, and if a component tries to draw more than that, it just wont work.

 

Maybe that's true in the laboratory, but in the real world there are a battery of things that can go wrong and effect the optimal performance of an electrical component.

I'm sure there's a lot of people out there that have had hair dryers, hot plates or irons that have overheated despite being UL approved. Granted, they're not nearly as sophisticated, but you'll have to pardon me if I don't give these devices (even with the electronic countermeasures) the confidence you suggest.

All ports at maximum draw? I'm not going to say you're wrong, but I just don't have that much confidence in any consumer electronic device. Wish you would test that theory though, and give us the results. Anyone?

 

There's in spec and out of spec. Most laptop ports are designed to permit out of spec demands because consumers want to use these devices. However, they tend to be non-computing devices. There's no risk in running an in spec device on a limited to spec port, but if either end varies varies, anything can happen.

 

I was just trying to understate the fact that you're not going to fry a motherboard for it. In fact, I remember several months ago when I had my macbook, and I used a 4 port USB hub (non-powered) to power my keyboard, mouse, and mobile broadband card. The booklet for the card specifically said to not use it in a USB hub. The worst that happened to me was I would occasionally get dropped connections and I'd have to unplug and re-plug the device back in to get it to work. I never had a fried motherboard. I stand by my statement. I just wanted to install some confidence and downplay false claims that you can actually damage your system from it.
However the best person to ask is Greg, since he's a computer engineer, and I invite him to weigh in on this.

 

Fine, but that wouldn't change anything as far as I'm concerned since he's unlike to guarantee a repair should something go wrong. Not that I'm saying it will, that's just my line of caution.

My point simple emphasizes my position on erring towards conservative. Some product understate their maximum capacities, while other overstate them. For example, how many people actually use all four ports simultaneously? You use one, then the other. In addition, manufacturers have long since mastered the art of clever language to market a product.

Just because your car has a speedometer that maxes at 130 doesn't necessarily mean that it can go that fast. Nor does a speaker rated at 100 watts peak, mean it can operate at that rating continuously.

What I'm trying to say is there's no right or wrong here, you just have more confidence in manufacturer's products than I do.