Asus m4a78 plus wont post

[jeffinak]

So my new motherboard finally arrived (after waiting a month and a half for Asus RMA), and after assembling everything: when I hit the power switch on the PSU the led lights up on the board, but when i hit the power button on the case I get a quick flash where for a fraction of a second the CPU and PSU fans begin to spin and light up but then they abruptly stop. I have been over several posts on the forums here and cant seem to find the answer to my problem. One more issue I seem to have encountered is that I do not have a motherboard speaker so if there is any beeps happening I cant hear them.

new board is asus m4a78 plus
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=asus+m4a78-plus&x=0&y=0

memory is adata 2x2 gig @ 800 mhz
http://www.newegg.com/Product/Product.aspx?Item=N82E16820211188

and new cpu is a phenom 2x3 740 BE
http://www.newegg.com/Product/Product.aspx?Item=N82E16819103699

also running an xfx radeon hd 4650
BFG 430 watt psu
and thermaltake duoorb cpu cooler

any help is greatly appreciated

 

[dark_lord69]

1. Did it work with a motherboard before you sent it in for RMA? If yes, then they likely sent you one that they "Fixed", only didn't acutally fix it. Most likely someone like you sent in a board, the underpaid techs pluged in the cables and after powering on and runing a basic test or two they boxed it back up and shipped it to you without any actual repairs. (This senario happens all the time.) If this is the case you need to get it RMAed again.

2. Did your motherboard have the same issue before you sent it in for RMA? If yes, then:
I. Remove one of the sticks of ram
II. Disconnect the SATA or IDE cable on all Hard Drives
III. Disconnect the SATA or IDE cable on all CD/DVD drives
IV. Remove all add in cards (Like sound cards and TV tuners)
V. Only keep the video card plugged in
VI. Make sure you have the main motherboard power connected (24-pin)
VII. Make sure you have the secondary power connected (4-pin)
VIII. Do not turn on the PC without a fan and Heatsync on the CPU.

After you've checked all of that and removed the extras down to the bare essentials. Power it on.
If it posts:
Reconnect items one at a time and see if it posts each time until you discover the cause.
If it still does not post:
Take out the stick of ram you currently have installed and put the other one in.
If it posts after that you had a bad stick of RAM. If it still doesn't post then I suggest you buy a "PC Post Card".

It's a card that you can install into a PCI slot that provides an error code. That error code can point you towards the right direction in discovering the cause of the issue. However, if you've tested both sticks of RAM then the cause is definitely one of 3 items. Power Supply, CPU or Motherboard. The point of the post card is that it can tell you the cause of the issue with less guessing.

It's possible to have 2 bad motherboards in a row so don't rule that out.
If you've had the same issue on both motherboards then I would suspect the Power Supply as the culprit. OR another possibility is the CPU. but I suggest trying a different power supply first. This last paragraph is assuming you've completed my troubleshooting steps above.

Good Luck, I hope this helps!

 

[ghost_florian]

Dark_lord69 is right, manufacturers often ship you your part back...

What happens after the fans spin and then stop ? Does the computer POST ? Or does it just die without any last wish ?

 

[jeffinak]

It seems apparent that the board I got was at best refurbished as it came in a plain white unlabeled box as opposed to the Asus box the original came in. I was lucky enough to have an extra psu laying around, once swapping them out the computer starts up, all fans spin (cpu, case fans, and video card fan) and all lights come on, but there is no signal sent to the monitor. Again I have no mainboard speaker so with no signal to the display I am unable to tell if it is posting or not at this point.

thank you so much for your help so far guys

 

[T_T]

Power up w/o display is a classic tell-tale sign of a case short. Try breadboarding your rig.

1. Remove all connections to the mobo.
2. Take mobo out of case.
3. put mobo on a non-conductive source.
4. Install one stick of RAM.
5. Connect PSU P1 and ATX power connectors.
6. Install GPU and connect display (DVI/VGA) cable.
7. Use a flathead screwdriver to jump the PWR_SW pins on the mobo.

If you get a display, then there was something in your case causing the short. Look for any unused standoffs.

 

[jeffinak]

I tried doing the breadboard thing....I used the box the board came in with the antistatic bag flattened out under it, but am still having the same issue, as soon as I jump the power switch everything lights up and all the fans spin, but still nothing to the display, I know the card is good, in fact at this point the only not "known goods" are the brand new cpu (phenom 2x3 740) and the board that was shipped back after being "repaired", but the issue I was having when I rma'd the board is no longer present (no lights, no power at all)

 

[T_T]

All right. Completely remove the heatsink fan. Take a case fan and connect it to the CPU fan header. Power on the system. Does the case fan over the heatsink spin properly?

 

[jeffinak]

the cpu fan I have doesnt really have a heatsink and seperate fan, there are five copper heatpipes directly connected to the two fans on top

http://xoxide.com/thermaltake-duorb-cpu.html

if I unplug this from the pins I'm afraid i might fry the cpu when I power up

 

[T_T]

ahh, sorry. I missed that from your original post. Clear your CMOS, then reinstall the stock heatsink and fan assembly. Basically, what I am curious about is whether or not the CPU fan header works properly.

 

[jeffinak]

I have cleared the cmos settings, unfortunately I no longer have the stock AMD HSF, if it helps any the cooler I do have on there lights up and spins correctly whether plugged into the cpu header (4 pins) or the power fan (3 pins) header. funny thing is now that its on the box, the other psu seems to be working again as well (no longer almost starting the fans but acting exactly the same as the replacement psu)

 

[T_T]

Short of truly having a f***ed up mobo, RAM is the next likely suspect. See if you can borrow RAM from a friend.

 

[jeffinak]

well, I tried using a different stick of RAM (was working fine in the same model board) but still no joy. Was really hoping it wasnt the board again, but the only thing I havent done yet is to try replacing her 740 with my 955 to see if it works then, but from what I understand if it was the cpu then wouldn't it shut the system down?

 

[T_T]

In my experience, a bad CPU can cause the problem of "no display", but I've only encountered a bad CPU once; it was an AMD Sempron. Yes, it was a looooong time ago. As a last resort, I would try a known working CPU on the RMA mobo. If still nothing, send another RMA request in.