bad psu running fans but not system?

[inquisitor1]

im trying to help someone rule out a bad component. guy at the pc shop told him the MB is bad so quickly bought one when I told him to wait and rule out other parts first. I didnt think it was mb. it still wont post after new one. providing he even connected it properly

he has a z170 mb and he doesnt know what cpu he has which might have a igpu. its not posting but fans are turning on. im not certain the psu is good just cause it turned on some fans. a bad car battery may turn on headlights and dash but not enough to crank engine over

I told him take gpu out. take out his psu from other pc and just connect 24pin and 8pin connectors and connect monitor to io shield hdmi of igpu and see if it posts. then he can connect old psu and see if it still posts. if it doesnt then psu. if it does then probably gpu card.

but hes going to spend more money to get it analyzed. the guy screwed him twice. sold him mb that he didnt need, and sold a z170 with ddr3 instead of ddr4 then wants $120 to rule out the issue. I laughed at him. its funny when they dont listen.

whatever. he has another pc with psu. I told him he can check himself. guy is an idiot. I need to get smarter friends.

 

[cvaldes]

I agree: find smarter friends.

 

[Frick]

I think you should get in touch with the repair guy and work with him. You can make good money scamming your friend, and if he's dumb enough to fall for it he deserve to get scammed. It's why I exclusively rob old ladies and children: they can't defend themselves and therefore deserve it.

If you actually want to help you either get over there and have a look yourself, or let him get on with it on his lonesome.

 

[inquisitor1]

It's why I exclusively rob old ladies and children: they can't defend themselves and therefore deserve it.

thats hilarious.

he lives 2 hours away. I sat with him on the phone and told exactly how he can check. he has another pc and he can easily check. take out gpu from bad pc, take out psu from other pc, connect 24/8pin and connect monitor to hdmi on rear mobo port and see if it posts. if it posts then either psu or gpu. then connect old psu and see if it posts. if it doesnt then psu, if it does, then probably issue with gpu. he uses display port. I told him try hdmi to test. my gtx970 display port doesnt work. I use hdmi with it. but against me telling him to do the check he purchased a mobo when I said a)he doesnt know what it is and b)I have a strong feeling it isnt the mb

it may even be some ram issue. he didnt rule out any part. if he lived near me then we would have figured out the issue.

the guy at the store took the ddr3 mb back and charged him for the newer revisioned ddr4 mb and said hell put the mb on sale and when it sells hell return his money. he paid twice for something he didnt have to, and now going to pay him to diagnose when he can do it himself easily. id more then happily video chat and help him. he keeps arguing that just cause the fans work, the psu is good. cool.

 

[Bill_Bright]

im not certain the psu is good just cause it turned on some fans. a bad car battery may turn on headlights and dash but not enough to crank engine over

A car battery is totally different from a PSU so not really a good analogy here.

It is not about having "enough".

Computer power supplies are required to output 3 voltages; +12V, +5V and +3.3VDC and those voltages are only allowed to deviate ±5% (Note a new ATX 3.x PSU can deviate -7% on the 12V output only).

So a PSU may be outputting 12V causing the fans to spin, but that does not mean the +5 or +3.3V are present.

So, yes swapping in a known good PSU is absolutely essential and that is what the shop should have done before even thinking about recommending buying a new motherboard.

I definitely would be having a talk with that shop.