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GA-MA770T-UD3P: No boot: 4-pin 12V connector / CMOS jumper?


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GA-MA770T-UD3P: No boot: 4-pin 12V connector / CMOS jumper?
« on: September 18, 2009, 11:24:49 pm »
Hi, I'm looking for some advice.

I'm having problems getting my new build to work. My build is based on Tech Report's Summer 2009 "Econobox" except I use an EarthWatts 430W PSU instead of an EarthWatts 380W.

My problem is that the system doesn't boot. There is no image on the screen and no beep. All the fans go, and I can hear the SATA devices spinning up. It does not even beep if I remove all PCI/PCIe cards and RAM. Naturally in this case I do not expect an image!

I suspect something serious is wrong with either the motherboard, CPU or PSU, or maybe some combination of all three.

Motherboard: Gigabyte GA-MA770T-UD3P rev 1.0
CPU: Athlon Phenom II X2 550BE
PSU: Antec EarthWatts 430W

There are two things I can think of that might be wrong - other than faulty parts or some installation error like shorting:

1. The PSU has a 4-pin 12V power connector, but the motherboard has an 8-pin (or 2x4-pin) socket. However I think this should be OK because the manual says on page 22 that 4 of the pins are "Only for 2x4 pin 12V". This wording implies to me that there is the possibility of using 1x4-pin connectors. I'm not sure why the manual would include that comment otherwise. Also posts on the net seemed to say that a single 4-pin connection will often be OK if the CPU doesn't draw too much power, and the X2 is rated at 80W. It is not some 120W+ CPU, for example. However the PC does not boot.

2. I wanted to clear the CMOS in case that was the problem. When I tried to do this I discovered that the clear-CMOS jumper was already in place (i.e. it had shipped in place). The installation guide had not warned that it needed to be removed during installation. But in the section on clearing the CMOS the manual advises against turning the computer on with the jumper in place in case it cause damage: "...before turning on your computer, be sure to remove the jumper cap from the jumper. Failure to do so may cause damage to the motherboard." Unfortunately I had already turned the computer on with the jumper in place this because I tested the computer several times before I thought about trying to clear the CMOS and noticed this warning.

What I'd like to find out is whether either of these are likely to be problems or whether I should start thinking about faulty parts or some other installation error. Should this motherboard/CPU combination work with a 4-pin connection? And what is the likelihood that the motherboard has been damaged by having the CMOS jumper in place while powered on?

If the power connector is likely to be the problem then I will order an EarthWatts 500W, which includes an 8-pin EPS 12V connection. I will try out the new PSU with the motherboard. If it still does not work then I will try a replacement motherboard.

If the 4-pin power connection is likely to work, but the CMOS jumper has probably damaged the motherboard then I'll get a replacement motherboard and try again.

If the CMOS jumper damaged the motherboard then ideally I would like it to be replaced at no charge because I feel the installation instructions should have highlighted this clearly as a potential problem. i.e. The fact that the jumper was already in place and needed to be removed before first boot. There is a page that lists installation precautions, and one more bullet point would have saved the board. I read all the upfront warnings carefully, but I did not pre-read the entire 91 page manual and check every jumper! But maybe this is something obvious that I should have known about. Feel free to share your opinion. :)

My feeling is that the motherboard is probably damaged and I should try to replace that first. But is there something else I should consider doing?

Thanks for all advice. Let me know if there's any more information I can give.

« Last Edit: September 19, 2009, 12:10:17 am by richd »


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Re: GA-MA770T-UD3P: No boot: 4-pin 12V connector / CMOS jumper?
« Reply #1 on: September 19, 2009, 06:01:04 am »
I've got this working now. It works after reseating the CPU and heatsink. Before I can use the PC I will need to get some more thermal compound to tidy things up properly, but for the moment I'm just happy to have it POSTing.
« Last Edit: September 19, 2009, 06:01:46 am by richd »


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Re: GA-MA770T-UD3P: No boot: 4-pin 12V connector / CMOS jumper?
« Reply #2 on: September 26, 2009, 02:33:11 pm »
Glad you got it sorted, get yourself some nice artic silver 5 thermal compound too ;D
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