Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a desktop computer which I put together myself and in the last weeks I discovered a strange behavior.

The same issue refers to three components independently. The onboard network controller, the PCIe sound card, and the intern USB3 upgrade card which is PCIe, too.

The point is that each of those three components either work or not after booting my computer. For example this morning I turned on the computer and USB3 worked, network and sound didn't. Therefore I rebooted and all three components work now. That will stay true as long as the computer is running. After each new start, it seems like a wheel of fortune whether one of those components is working or not.

The drivers are updated for all of those components. Here are my components.

  • Operating system: Windows 8 64 bit
  • Motherboard: Gigabyte GA 870a UD3
  • Processor: AMD Phenom II X6 1055T
  • Video card: NVIDIA GeForce GTX 660
  • Sound card: Creative X-Fi Xtreme Audio
  • USB 3 upgrade card: Sempre UP33-I19

Can you think of a reason for this strange behavior? At the moment I can work fine, but just need several restarts to get all needed components working. How can I narrow the problem down? How to approach such a problem?

Update: I doubt this issue has something to do with the power supply. I completely removed all unnecessary components like secondary hard drive and optical drive for testing with all other components being distributed as evenly as possible but the problem remains.

Generally, the situation became slightly worse. First, the USB 3 upgrade card doesn't work at all anymore. Second, the ethernet adapter doesn't get recognized in half of all boots. And even if it is, I often have to disable and enable the adapter under "network adapters" or "device manager" to get access to the internet.

Might this be a fault of the motherboard? What else could cause those components to not start up properly?

share|improve this question
Are there any other symptoms? Did the RAM pass a memtest86+ check? Is the CMOS clock keeping time? Does the system always power on reliably? – David Schwartz May 16 '13 at 10:24
@DavidSchwartz. I checked the RAM and the system always powers on reliably. I don't know how to check the CMOS clock, but the time in Windows is accurate since years. – danijar May 16 '13 at 10:27
up vote 1 down vote accepted

Sounds as if your power-supply isn't quite up to the job.
This causes some of the hardware not to initialize properly on boot.

On a reboot the system needs somewhat less power so you got just enough to get everything initialized the second time.

Most modern motherboards have an extra 4-pin or 8-pin 12V power-connector in addition to the normal 24 pin power-connector.
If your motherbaord has this then supply power to it. It usually feeds the PCI_Express bus.

share|improve this answer
Thanks for your answer, that sounds reasonable. On the other hand I think my power supply is quite good. It is a Cougar GX 600. Shouldn't 600 watts be enough for my system? I connected any additional power pin on the motherboard. – danijar May 16 '13 at 9:13
@danijar 600 Watt would seem enough yes. (Around 400/450 seems to be the max draw going from your specs.) Can you redistribute the HD and/or optical drives to other power-cords ? You can get similar issues if you try to draw too much from the same output on the PSU. – Tonny May 16 '13 at 11:12
It's been a while. The involved devices are soundcard, network controller and usb controller. All of them get their power from the mainboard directly. Additionally the usb controller has a own lane from the power supply. You are right, all SDD, HDD and DVD drive are on the same lane. Could that cause other devices to not get initialized? – danijar Jun 2 '13 at 16:16
@danijar That could indeed be the case. Anything might happen if you overload (part of) the powersupply, Most modern PC PSU's are so-called "switched" powersupplies (no transformer used) which is good for low leakage and 80+ specs, but also means that a slight irregularity on one output can de-stabilize everything. – Tonny Jun 2 '13 at 21:14
Hi there, I now assume that power consumption is not the issue here. Could you please take a look on the update of my question? – danijar Apr 19 '14 at 8:54

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.