New PSU, new motherboard but still no joy when I turn on power

[pantichd]

Hello,

A couple of months ago we had lightning strikes and several of our PCs were affected. I've replaced parts and all of them are OK except my son's PC.

When I push the power button nothing happens. No fans come on, no beeps, NOTHING!

So I thought the PSU was bad. Replaced it with a brand new one but still same result. Don't laugh at me now but I took it to Best Buy because my son insisted on having the Geek Squad look at it. So much faith from my son, eh!?
Anyway, they said it had to be the motherboard so I ordered him a new motherboard.

Just installed it and still NOTHING!

I have absolutely no idea what else to try. Can anyone give me some suggestions?

The configuration:
Processor:

http://www.newegg.com/Product/Product.aspx?Item=N82E16819115031

Original Mobo:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813127029

Original PSU:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153052

New Mobo:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813131296

New PSU:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817182010

 

[wahnula]

You were correct in assuming the PSU could be bad, but it was a reach to try a new mainboard so soon. Oh well, you have one, let's move on.

Asus usually has an LED on the board near the header pins that indicates if the board has power. All it takes to get this LED to light is connect the ATX 24-pin PSU connector and the 4-pin (or 8-pin) additional power connector and hit the PSU's I/O switch. Do you have one of these LEDs on your mainboard (should be identified in the board map page)and is it lit in the above scenario?

Tony

Users helping Users...

 

[pantichd]

Hey Tony,

Thanks for your quick reply!

Yes, there are two onboard "buttons". One for turning it on and one for resetting it.

Both are lit but nothing happens when I push either one.

I wondered if it was possible that something was wrong with the power switch cable from the front control so I disconnected that, the hard drive, DVD drive and floppy drive. Then I tried the buttons again. Still nothing.

David

 

[BadBigBen]

Things to check,

1. Seating of the RAM modules...
2. seating of the GFX-Card, slight variance can cause a no post...
3. Clear the CMOS, some mainboards do not like being moved...
4. check the HeatSink fans, if they are plugged into the correct connector... if the mainboard notices that a fan is missing, it will not POST to prevent damage to the CPU...



Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."

 

[wahnula]

Both are lit but nothing happens when I push either on

Great. That means the PSU works and the mainboard works. Next we need to add one compnoent at a time until we see what the culprit is. I would do a "bread-board" build, outside the case with the M/B sitting on the box you bought it in, outside of the case. No HDD, no ODD, no USB, NO FDD, no card readers etc.

All you really need to POST is a CPU (w/ HSF), RAM, and a video card. If it's a modern video card make sure the PCI x 6 or PCI x 8 is connected too. Take a small, flat-blade screwdriver and CAREFULLY short across the PWR headers on the Asus or use the built-in switch. The less connected at this point the better.

First, make sure your CPU is approved for that board. If so, remove all system RAM but one stick, and double-check the seating of the video card. If no joy, start swapping out RAM sticks one by one, but I'm betting on the graphics card.

If you can "borrow" a vidcard from a friend or local Fry's or the like (not top-of-the-line, just workable) and it turns out to be the problem then you will be spending lots more on a "correct" video card for this system. If not you will be eating the "restocking" fee, so keep every tiny piece of the packaging.

If no go there...and you have checked more than one stick of RAM (everyone could always use another!, then it's time to try a CPU swap. Get a list of the acceptable CPUs, if it turns out to be the problem you will have TWO working systems. This is where the home repairman falls down; without a years-long accumulation of parts, you will have to borrow or buy test parts. My only advice is to keep ALL the original packaging for immediate resale on eBay.

Your new M/B will accept a 45nm Penryn CPU, that's enough reason in my book to upgrade. Keep us posted!

Tony

Users helping Users...

 

[pantichd]

Thanks Ben and Tony.

I'm in the middle of some things this morning but I'm going to try your suggestions this afternoon and post my results.

I didn't realize that bad memory or video card could cause such symptoms. I always thought that at least the PSU, CPU and case fans would come on and that you'd get some beeping if memory or video card was bad.

David.

 

[BadBigBen]

Ah, those where the old days... brings a tear to mee eye... LOL...

Tony pretty much summed it up, on how to proceed, can't go wrong there...

Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."

 

[Johnthephoneguy]

Could it be the momentary power switch also? Maybe when you are pushing it, if it had problems it wouldnt work, you might have to short the pins on the MB.

JohnThePhoneGuy

"If I can't fix it, it's not broke!

 

[pantichd]

OK, here goes a stupid question but I have to ask... By "short the pins" you just mean put something metal like a screwdriver so that it touches both pins, right?

 

[BadBigBen]

Pantichd, Yep, correct...

Ben

"If it works don't fix it! If it doesn't use a sledgehammer..."

 

[wahnula]

It's a momentary contact switch, and so is the reset switch. Like a doorbell, not a room light.

You can safely short across the pins of either header, but that switch on the mainboard rules out a bad switch, unless BOTH are bad...highly unlikely.

Tony

Users helping Users...

 

[pantichd]

Well, it's the videocard! Grrr!

I feel really stupid now. Can't believe that I didn't think of just trying it without the video card.

Oh well, I guess now I gotta see if Newegg will let me return the new motherboard.

Man, what a mess!

Thanks everyone for all your help.

 

[wahnula]

I'd keep new mainboard and eBay the other. There was a method to your son's madness with using the Geek Squad after all!

Oh well, don't want to start a domestic issue, Newegg will return minus 15%. Cry a little bit and they might waive it.

Tony

Users helping Users...