Hi

I wanna consult your expert opinions on this problem I recently started having in my PC.

Here are some quick facts:

Type/Manufacturer: Fujitsu Siemens SCALEO T (fujitsu-siemens.com/products/deskbound/personal_computers/scaleo_t.html)
Date of Purchase: About 1 year ago
System Specs [PDF] (http://server-uk.imrworldwide.com/cgi-bin/b?cg=COM-complete&ci=siemensfujitsu&tu=http://www.fujitsu-siemens.com/Resources/82/86632539.pdf)

My problem is the following:

I own a USB portable harddisk drive (60 GB). If I try to hook up this device to the computer before or after starting the computer, the computer will shut down or wont start. It's as if the harddrive is sucking up all the power or something. If i remove the USB drive, the computer will start normally.

Anohter USB-based device, my ADSL modem, presents similar problem. If I start the computer with this device hooked up, the computer will keep restarting infintely before logging on to the OS.

Note that other USB-based perepherial devices (such mouse, keyboard, bluetooth, web camera) work just fine.

I have tried the two devices that are causing problem (my USB harddrive and ADSL modem) on another machine and another laptop. They work just fine.

I started suspecting that the reason why they're causing problem is that they might consume relatively more power than the other simpler devices (e.g., mouse and keyboard). And so this problem is either a power supply problem or fearfully a motherboard problem. But I just can't figure out which.

Have you guys experienced anything like this awkward problem or do you have any suggestions ?

Any help would be appreciated.

Thanks!

It is the power suply. It can not give you enough power on 5v line.

It is the power suply. It can not give you enough power on 5v line.

I really sure hope so. But how did you conclude that it's not related to the motherboard ?

Plug the suspect devices into a powered USB hub, and the hub to the computer. This should take the USB power load off of your machine, so if things work normally, this means that the USB power load was the issue.

You should be able to pick up at least a USB 1.1 powered hub for less than $20 retail (less than $10 online), and while the 1.1 speed of 1.5 Mb/sec is relatively slow, it's still as fast as most DSL, and fast enough to support MPEG4 video playback.

Also note that if the machine was working with these things plugged in before, and work now on the hub, then it may mean that iether one of the devices is failing, or that your power supply is dying.

Plug the suspect devices into a powered USB hub, and the hub to the computer. This should take the USB power load off of your machine, so if things work normally, this means that the USB power load was the issue.

You should be able to pick up at least a USB 1.1 powered hub for less than $20 retail (less than $10 online), and while the 1.1 speed of 1.5 Mb/sec is relatively slow, it's still as fast as most DSL, and fast enough to support MPEG4 video playback.

Also note that if the machine was working with these things plugged in before, and work now on the hub, then it may mean that iether one of the devices is failing, or that your power supply is dying.

Awseome idea!

I'm gonna try and see what I get.

Thanks!

Just to follow up on this issue for those who might get such a problem in the future:

Totally a power supply problem!

The technicians at my local Fujitsu Siemens service center overlooked (or probably lied) about testing with a different power supply and went ahead and ordered a new motherboard for the machine. It took 2 weeks to arrive and when they installed and declared the system working, I took it home and the same problem happened!

Furiously, I took it back to them the next morning. It took them another week to let me know that it turns out it's a power supply problem and they changed the power supply and it worked.

It was such an obvious call from the beginning. But i'm guessing they wanted to make more money with a new motherboard order. I'm not sure. But whatever it was, I'm totally unsatisifed with their level of service and would probably not purchase a Fujitsu Siemens device in the future unless it came with more than 1 year of warranty.