Motherboard power on without switch

**judderman** · October 26th, 2009, 04:50 PM

After a problem with my old system, I upgraded but am stumped with this problem

Got the Motherboard on the bench, it's a Gigabyte GA-MA770-UD3
Using an AMD PHENOM X4 QUAD-CORE 9650 2300MHZ 4MB 95W AM2
With GeForce 9600GT, 1GB, HDCP, HDTV, PALIT Graphics card
And 1 stick of 2GB Crsair Memory

Powers up as soon as I switch on PSU without the power switch involved

Now, Iv'e tried everything I can think of -
Different PSU
Different Proccessor
Different Memory, Different memory bay
Different Graphics Card
No power switch connected

Have made sure nothings shorting out and the board looks physically fine, but I'm sure I came across this problem years ago on another build.

Any Ideas ?

Thanks,
Stephen

**Aaron_8015** · October 26th, 2009, 04:56 PM

Have you tried reseting cmos?

**stroyal** · October 26th, 2009, 05:14 PM

I've got a Dell that does that the first time I boot after the power supply is unplugged and reconnected.
It works normally after that, until I unplug it again.

**judderman** · October 26th, 2009, 05:49 PM

Thanks for the quick reply - just tried taking the battery off and cleared it for 20 mins but still the same

**Steve R Jones** · October 27th, 2009, 06:07 AM

Look in the BIOS for the settings "What to do in the event of a power failure." Set it to do nothing.

Also look for wake on lan and make sure it's disabled.

**judderman** · October 28th, 2009, 03:09 PM

Wish I could get to the bios to change something - the board powers immediately, without manipulation of the Power Switch pins - so there MUST be a short circuit somewhere on the board and this does not allow a video signal to get to the monitor

**masterdelta** · October 28th, 2009, 07:09 PM

You should rather have 2 sticks of 2x1GB memory, as dual channel (having two sticks of RAM in the correct slots) work a lot faster. You should purchase another 2GB stick if you want to get the best performance. Also consider installing 64-bit, Phenoms support it and 64-bit gives you much memory advantage.

**stroyal** · October 28th, 2009, 09:11 PM

Originally Posted by masterdelta

You should rather have 2 sticks of 2x1GB memory, as dual channel (having two sticks of RAM in the correct slots) work a lot faster. You should purchase another 2GB stick if you want to get the best performance. Also consider installing 64-bit, Phenoms support it and 64-bit gives you much memory advantage.

I might be a good idea to fix the OP's computer, before you worry about upgrading it.

Edit" Any test I have seen, dual channel is only slightly faster, and there is no advantage to 64bit, except the extra memory that most people don't need yet.

**Steve R Jones** · October 29th, 2009, 06:08 AM

Originally Posted by judderman

Wish I could get to the bios to change something - the board powers immediately, without manipulation of the Power Switch pins - so there MUST be a short circuit somewhere on the board and this does not allow a video signal to get to the monitor

Hold down the DEL key or whatever the key is for the BIOS before hitting the power.