A7V system is dead

[Guest]

T-bird 800
Asus A7V
Asus 7700 Deluxe
Creative Live! Player 5.1
IBM 46.1 Gb 75GXP
Plextor CD-RW
Samsung DVD
NIC
300W power supply

I've just put together a new system and it won't start.
No fans start, no beeps, nothing appears on the monitor.
Nothing happends at power-on. The the green on-board led, PLED
is indicating power-on/soft-off as soon as the power supply is
connected to the wall.

My first thought was that the ATX power switch was not coreectly connected to the mobo.
Checked it. Checked all jumpers several times (haven't even touched them,
all are in jumper-free mode). Disconnected all IDE + Floppy cables. Checked that
the CPU was correctly inserted. But no change.

I don't have any other system to test the indiviual components in. Anyone who knows how
the mobo would act with a faulty processor inserted into the socket? Or how I can simulate
an ATX power-on signal manually on the PWR switch connector? Just to shorten it with a jumper cap?
Or how to test if the ATX power switch is working properly?

What components are necessary for the mobo to show anything at all on the screen?

Any ideas what can be wrong?



Your help would be greatly appreciated, thanks in advance!


cloun

 

[Guest]

In order for an ATX system to boot, you need:
1) Processor (+heatsink, fan)
2) RAM, securely in its socket (you do have RAM, right?)
3) Video card, securely in its socket
4) Keyboard is recommended but optional
5) Power to the board (which you have, unless the LED on the motherboard is getting power from something else)
6) Soft-power switched by shorting the appropriate pins on the motherboard

With a brand-new system, the most likely problem is a loose connection to the video or RAM.

When I setup a new system, I only connect the bare essentials (1-6 above) and do so with the motherboard on its antistatic bag (not screwed into the case) to eliminate any possible problems there. Once the memory has been counted and the BIOS complains about not having a boot disk, I install the barebone parts in the case, connect the LEDs and floppy, hard drive, and CD-ROM and install the OS. Once that's successful, I add the cards one at a time and install their drivers.

Good luck.

 

[Guest]

Thankyou for your reply.

Yes, I have 256 Mb PC133 RAM inserted into slot 1.

Also just tested the power switch with a multimeter. It works just fine.

Will try to remove some more components/check insertion of ram once again. Or maybe try w/o ram and vcard as well to see if the mobo gives me a few beeps as stated in the manual.

cloun

 

[Guest]

Have tested with minimal number of components now. Same result.

When I connect the CPU-fan directly to the power supply it moves a little when pushing the power switch. But only the first time after the power supply is connected to the wall.

So, is it the mobo or the CPU that is broken? Anyone who knows how an A7V shold behave without/(with broken) CPU inserted?

cloun

 

[Guest]

If your CPU fan is not running you have a POWER problem not a boot problem.

The PS could be bad. The power supply is latched on after the MB sends it a Power Good pulse. This pulse is generated when ALL of the voltages have reached at least 75% of their nominal values. If this doesn't happen within x miliseconds the supply shuts off.

The power on switch is made only as long as you push it, right? ATs were latch on latch off, doesn't work on an ATX.

As this is a new build, I would suspect that the MB is being grounded and shorting something.

Remove the board and place it on an insulated surface. Connect the case front panel wires (Colored wires are +), Video, Mem, CPU and Power supply.

If it comes up now, look for incorrectly placed mounting studs. Use ONLY the ones that align with the MB holes ringed with solder.

If it Doesn't power up, (look at fan and Pwr LED) you can try it without Vid.card and Mem. and probably CPU but I'm not sure of that.

Spare parts are really the only way we amateurs can trouble shoot these things. Swap till you Drop! I say.

Good luck

"I THINK I USED TO KNOW THAT"

 

[Guest]

I bet its this.......

Make sure the LED'S are on the motherboard properly for the power switch.......

i bet thats it
and if its in properly try turning it opposite backwards
thats prolly it

also mane sure your baord is grounded properly with those brass screws under the board and make sure no metal is touching

-- They have found a way to harness the power of a thunderstorm and expell it with great force!--

 

[Guest]

Now I've tried with the mobo on an insulated surface. Same result as before. The front panel button is doing its job and an extremely short pulse is sent out from the PS to the 12V wires but nothing more happens. Same result with/without CPU etc.

Any kind soul who is willing to test how their A7V mobo behaves without CPU connected? Anyone who has a damaged CPU to test with as well?

Or any suggestion on how to determinate if the PS is bad?Unfortunately I don't have any more ATX PS.

 

[Guest]

Unfortunatly you are at the point where substitution is the only solution.The problem is either the PS or MB. However there maybe someone out there in Cyborland that KNOWS how to test a power supply. Maybe a post in one of the Technical Forums can scare them up. At any rate keep us informed.

Do you have someone that would let you try your PS in their PC?
Do the people that you bought your stuff from offer any Tech support?

I have been in this posistion and bought another PS to test. It didn't fix my problem but at least it proved that I had a bad MoBO.

Good luck and let me know what is happening.

"I THINK I USED TO KNOW THAT"

 

[Guest]

I have to agree with zignif, it is not uncommon to get a bad power supply or motherboard right out of the box. i have ran across both myself (i buy alot of my parts at computer shows but i have also bought a motherboard from a retailer that was bad right out of the box). Unfortunately the easiest way to troubleshoot would be to swap the power supply with a known good one. keep in mind if you buy a new one just to try, most retailers won't allow you to return it. I would first try the really simple things first, such as; the ac voltage comming from the wall socket, the power cord, the surge protector, any fuses or resets in the surge protector or the power supply itself, if you have a voltmeter check that each pin in the atx connector is giving out the proper voltage-especialy the power-ok pin. also visualy inspect the board the best you can for and bad traces or apparent damage. hope this helps, john

 

[Guest]

my tbird 800's ps just died today, replaced it, and i'm back up- i would get keyboard lights to light up when it plugged in, but no go when the switch was hit (it worked for 6 months)...my vote is with the power supply...

 

[Guest]

are you sure the switch on the back of the power supply doesn't say 220/230V? it should be 115 or 110V. i usually see a fan jolt for less than a second and no power afterwards whenever it was at 220 or 230V.

 

[blah]

Oh, my child, repent, get the good PS and be blessed... hehehe

Post, we'll do the "search"...