New Home-Built Computer Power Problems? (Computer 2)

Bought the kids DIY computers for Christmas. One is working, one is not. Here's what we are working with:

MB: MSI 970A-G46
Video: Geoforce GTX 650
Processor - AMD FX 8350 8-core Black Edition
Power Supply: Corsair CX500M

I've checked and rechecked the wiring. It powers up weird. Like I mentioned, I have a twin machine that's working, so I sort of know what it should look like.

When I power on the machine, the fans start running, but we get no video to the monitor. The power LED on the front does not light, and the power button on the front of the machine will not turn the machine back off. I pulled the switch assembly off and tested it on the known good machine. It's fine.

So, what should I try next?

 

Re: New Home-Built Computer Power Problems?

Yes, I started a different thread to keep the issues separate. It was too confusing talking about two machines in one thread. The other one is now working fine.

 

Are you sure that you have enough PSU power.

You said that your PSU is 500watts I all so have a MSI 870A-G54 mother board military class version and i run a 4 core processor.I think the issue could be that your 500watt psu is not up to the task of the requirements.Your Fx 8 core requires 125watts alone.

Same as my quad core and you said that you have a Ge force GTX 650 i have a EVGA GTX 550 ti minimum requirements is 400watts so as you can see you are most likely pushing your PSU or not enough as is.

I would run at lest a 550watt or 600watt psu in that system.

 

I hear what you're saying, but I am not pushing it at all yet - it isn't even running yet.

 

That is way it is not running not enough juice.

1. Power supply Can burn out from to being overloaded, and possibly fry other components. Whoever said it won't obviously hasn't build a computer before.

2. Things will overheat, when its underpowered everything can not run how it should meaning your GPU/CPU fan will not run at proper speeds and will allow the CPU/GPU to overheat.

 

Hello,

You said your power LED does not light, did you plug in the "Power LED" tiny wire in the correct place on the motherboard?

A 500 Watts PSU like that is more than enough for that setup:

650 (non ti) - Has a max TDP of 64 watts (An EVGA 550ti like MetaWard has, consumes almost twice the amount).

http://www.hwcompare.com/13482/geforce-gtx-550-ti-vs-geforce-gtx-650/

AMD FX 8350 - Max TDP of 125 watts

So GPU and CPU alone suck in 189 watts together running at full speeds. I doubt the rest of the system is using the other 311. Power output ain't the problem here, but doesn't leave out the possibility that it may be a faulty PSU.

Turning on a machine with no video can also be caused by other hardware such as Ram. Since you have another PC with identical parts you could borrow the Graphics Card, the Ram and the PSU which are the most common causes to a non booting system.

A bad Motherboard or CPU can also be a factor although a CPU is rarely the cause.

 

Assuming a quality supply from a reputable maker, I agree.

And typically, both running full speeds at the same time would be a rare occurrence.

Most folks, even experienced builders, would be surprised at how little their systems draw. I recommend everyone buy (or at least borrow for now)a "good" UPS with AVR, one like this APC BR1500 or this CyberPower CP850 that have LCD readouts showing just how much power they are consuming.

Note I have an 3770 i7, 16Gb RAM, GTX650Ti graphics, 2 HDs, 1 SSD, network modem, wireless router, 1Gbit switch, and TWO 22" Widescreen monitors hanging off my UPS and right now and I am drawing just 190W from my 620W Antec PSU.

To be sure, use the eXtreme PSU Calculator Lite to determine your minimum and recommended power supply unit (PSU) requirements. Plan ahead and plug in all the hardware you think you might have in 2 or 3 years (extra drives, bigger or 2nd video card, more RAM, etc.). Be sure to read and heed the notes at the bottom of the calculator page. I recommend setting Capacitor Aging to 10% and setting both TDP and system load to 100%. These steps ensure the recommended supply has adequate head room for stress free (and perhaps quieter) operation, as well as future hardware demands. Setting Capacitor Aging to 30% will provide an even nicer amount of headroom. And remember, the computer’s components will only draw what they need, not what the PSU is capable of delivering. And the PSU will only draw from the wall what the computer demands, plus another 15 - 30% due to PSU inefficiencies. Buying way too big hurts only the budget. If you do need a new PSU, make sure you buy a supply from a reputable maker and that it is 80 PLUS certified. I prefer Corsair and Antec PSUs.

Note when I plug into the calculator the OP's specs (MSI 970A-G46, Geoforce GTX 650, AMD FX 8350 8-core Black Edition, then add 16Gb (4 x 4 DDR3) of RAM, 4 120mm fans, 2 SATA drives, 1 DVD, and bump up the variables as noted above, I get 346W minimum and 396W recommended for 10% capacitor aging, and 409W and 459W recommended with 30% capacitor aging.

So, assuming that Corsair 500 is working properly, it is plenty big enough for that system.

 

Yes, I rechecked the wiring several times. I even pulled the switch assembly off the case and wired it into the other unit, since that was the easiest thing to check.

I have also swapped the graphics cards back and forth, so I am sure that is not it. I will do PS and RAM today after I've had some more coffee. I hope it isn't CPU - that heat sync was a b***h .

 

I suggest trying out the Ram first, easy to remove and install than the PSU's never ending wires