Bad PSU??? 12 V only 9.9??

[MrEd]

I am trying to solve an issue with a "not so good" PSU. CX750M. My tester says it has the 12V, but when using HWmonitor, it says only 9.9V. My computer only runs for about 5 mins and then the CPU fan kicks up to 99% but temp only at 36. (high low at 29/52). After fans run at 99% for a minute or two the computer shuts down.

Question is this:

• Do you think it is a bad PSU?

Previous issues are this:

• bought prebuilt
• 500W PSU burned out
• Replaced PSU with CX750M from best buy
• Ran for a couple of months
• Seemed to be very hot from time to time, but I was blissfully ignorant
• Started randomly shutting down once every couple of days

 

[Nebulous]

Your best bet to be sure is to check the rails with a digital multimeter. Software readings are not 100% accurate for checking the rails on a psu. Also if your psu is running hot, means it's at it's power delivery limits.

If planning on a replacement, go for EVGA's G2 units. Best power supplies on the market now.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817438017

 

[diaz]

It may be worthwhile to establish whether or not there is another culprit causing the PSU to operate at its limit. Changing the PSU might not fix the problem..

 

[Silver_Pharaoh]

Your best bet to be sure is to check the rails with a digital multimeter. Software readings are not 100% accurate for checking the rails on a psu. Also if your psu is running hot, means it's at it's power delivery limits.

If planning on a replacement, go for EVGA's G2 units. Best power supplies on the market now.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817438017

+1 to both checking with a multimeter and EVGA's G2 lineup. Solid PSU's.

 

[ATMINSIDE]

Your best bet to be sure is to check the rails with a digital multimeter. Software readings are not 100% accurate for checking the rails on a psu. Also if your psu is running hot, means it's at it's power delivery limits.

If planning on a replacement, go for EVGA's G2 units. Best power supplies on the market now.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817438017

All this, +1

What's your system components, MrEd?
The G2 comes in 550W through 1600W, and they're all fantastic. If you list out your components we can suggest the proper size.

 

[Mr.Scott]

It's not the PSU.
It's a heat issue.

Specs for entire system please.

 

[ATMINSIDE]

It's not the PSU.

Specs for entire system please.

+1, I don't think it sounds like the PSU either.
More like a motherboard issue.

 

[MrEd]

Your best bet to be sure is to check the rails with a digital multimeter.

I measured at the plug that goes into the MB. Not sure what "check the rails" means. I checked the output on the PSU 12V 5V and 3.3V all good. So if this measurement is the same as "rails", I guess my PSU is ok.

 

[Mr.Scott]

+1, I don't think it sounds like the PSU either.
More like a motherboard issue.

Yes. Somethings getting hot. Not the CPU either.

 

[ATMINSIDE]

Yes. Somethings getting hot. Not the CPU either.

Yep, still waiting for system specs though :/

 

[MrEd]

I am thinking it was heat that damaged something on the chip or the MB also. Specs are:

Build by IBUYPOWER
- AMD Vishera FX-8320 3.50GHz
- 8GB DDR3 Memory
- 1TB HDD - DVDRW
- 2GB AMD Radeon R7 250
- Windows 8.1 64-bit
- stock 500W PSU

This build ran for a month or so, I was not thrilled with the gameplay, so I bought a used GTX970 from ebay. Then the stock 500W PSU burned out. (smelled and PSU tester came up dead).

Purchased CX750M at Best Buy.

 

[ATMINSIDE]

I am thinking it was heat that damaged something on the chip or the MB also. Specs are:

Build by IBUYPOWER
- AMD Vishera FX-8320 3.50GHz
- 8GB DDR3 Memory
- 1TB HDD - DVDRW
- 2GB AMD Radeon R7 250
- Windows 8.1 64-bit
- stock 500W PSU

This build ran for a month or so, I was not thrilled with the gameplay, so I bought a used GTX970 from ebay. Then the stock 500W PSU burned out. (smelled and PSU tester came up dead).

Purchased CX750M at Best Buy.

You left out the key part, what motherboard and cooler?

 

[MrEd]

I am ready to start over with a custom build from whatever I can salvage here --- OR --- Send it back to IBUYPOWER for a warranty repair. BUT I fear they will reject it with the non original PSU

 

[ATMINSIDE]

If you still have the old PSU, just drop it back in and then send it for warranty.

 

[MrEd]

Sorry, newbie here...

MB looks like Gigabyte GA-78LMT

 

[Mr.Scott]

Put the old PSU back in it.
IBUYPOWER is pretty good about stuff like that. Call them.

EDIT- That board isn't good enough for an FX. The board is done.

 

[ATMINSIDE]

Sorry, newbie here...

MB looks like Gigabyte GA-78LMT

There's your problem.
Replace the motherboard with one that has a proper VRM or do a CPU/mobo upgrade.

 

[MrEd]

I don't have the original PSU anymore.... unfortunately, and it looks like it will cost about $40-50 to ship back... tired of putting money into 3 month old machine, getting frustrated....

(I already called and have an RMA, so I could still do that)

 

[Mr.Scott]

Call them. You might be surprised.

 

[ATMINSIDE]

I don't have the original PSU anymore.... unfortunately, and it looks like it will cost about $40-50 to ship back... tired of putting money into 3 month old machine, getting frustrated....

Call them and explain the resets, they may still help you even without the original PSU.
That said, the motherboard is 100% the problem.