Home built computer keeps rebooting




I built a computer last spring and since the beginning it rebooted from time to time. This was rare enough not to be a big bother though. It has been doing it more and more over time though.

I have now disconnected the graphics card (ati radeon hd 5770) but it *still* keeps rebooting a lot. I'm currently on ubuntu and my specs are:

Item: AMD Phenom II X4 945 3.0GHz Socket AM3 6MB L3 Cache Retail Box Processor

Item: Asus M4A785TD-V EVO 785G Socket AM3 onboard DVI VGA HDMI 8 channel audio ATX Motherboard

Item: MSI HD 5770 1GB GDDR5 DVI HDMI Display Port Out HDCP PCI-E Graphics Card

Item: LG GH22LS50 22x DVD±RW SATA DL & RAM + LightScribe Black - Retail Box With Software

Item: Samsung HD103SJ Spinpoint F3 1TB Hard Drive SATAII 7200rpm 32MB Cache - OEM

Item: NZXT Gamma Black Mid Tower Case - No PSU

Item: CoolerMaster 600W Silent Pro Modular PSU - 50A Single Rail 9x SATA 2x PCI-E

Item: 2-2GB 240-PIN DIMM 256Mx64 DDR3 PC3-10600 UNBUFF (from crucial.co.uk)

I'd be very thankful for any suggestions as I need this computer for simulations now and can't have it crash!!




Oct 1, 2009
Have you checked your temps? The way you are describing it sounds like your system is resetting due to overheating. As you say it happened less frequenetly at first, and has now increased (which could be due to dust build up or dying fans).

I'd suggest you run prime95 / intelburn test and monitor the temps. This will push your cpu to the max and let you know if you are indeed having heat issues.

Worth ruling that out before you look elsewhere.

Another good thing to do would be update your motherboards bios and ensure that your network/sound/graphics drivers are all upto date. You can find the model and manufacturers of your network/sound via your motherboards homepage.


Aug 10, 2011

Thanks for the messages guys. I checked my ram and temp and they're both OK. When I take my 5770 out and use the graphics card on my MB everything works fine - no reboots. So it really must be the graphics card.

The computer sometimes even reboots in DOS while booting, so I don't think it's a problem with Windows. Ubuntu doesn't even load with the graphics card - I don't think it reckognises it (seen lots of problem posts about Ubuntu + 5770 online).

I'll keep looking - but any feedback is much appreciated!