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No LEDs, No Display, Fans work great, though!

1086 Views 19 Replies 4 Participants Last post by  IJzerenPaard
SO. This was a new build for me. The thing is, it worked great for about a month before I looked at the CPU temp and noticed that it was quite hot. I turned off the computer and disconnected everything (My computer is caseless) and took off the CPU fan. I removed the old thermal compound and replaced it with this new stuff I bought. I hooked everything up to the mobo, power supply, cpu power, cpu fan, video card, etc etc etc. I turned the power on by connecting the two pins on the mobo with my screwdriver and the fans spun up, but the monitor did nothing. There are two LEDs, a red one and a green one. The red one lights up when the computer is on and the green one lights up when there's power, but the computer is off. No LEDs were lit up when I started up the computer the first, second, or third time, yet the fans ran every time. The motherboard is getting power, but there's no LEDs and no BIOS display or anything. Pretty much just the fans, CD drives, and HDD.
I've tried doing the CMOS thing, both switching the jumper cap and removing the battery and replacing it after twenty minutes. I'm sure it's probably something stupid that I'm missing, but I can't possibly think of anything else. D:

I have a Biostar G31D-M7 mobo with an Intel c2d processor. 4GB of DDR2-800 RAM, an HIS Radeon HD5450, and a 400 W power supply.
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My first suspect is your power supply. It's underpowered for what your running.. You should be at a minimum 550w quality PSU for your setup, but i would suggest a 650w PSU.
But it worked great for a whole month! Are you sure?
Is the PSU a cheap generic one? We don't recommend anything less than a quality 550w PSU and up (depending on graphics card used) for any PCI-e graphics card.
But wouldn't the LEDs still come on even if the PSU was underpowered?
What Leds are you referring to. The monitor Leds has have nothing to do with the PSU. Does the motherboard make any beeps? You still haven't said the make of PSU. There's no doubt in my mind that your PSU is underpowered for your setup! A cheap 400w PSU will be lucky to provide 300w under load and when cheap PSU's die they can take other hardware with them.
The I just went to a computer store and bought the cheapest 400W power supply I could find. I'm guilty of that, for sure. I honestly can't remember the make, I'll post it when I get home today.

I'm talking about the power LEDs on the motherboard that turn on when it is getting power.
But if fans and drives all spin up, even the CPU fan, why wouldn't the LED's come on at least?
Does the motherboard make any beep codes? The PSU is by far the most important PC component as it powers everything. It should never be the sacrifice made in lowering the overall cost of a PC. In the end it usually costs alot more in replacement parts cause cheap PSU's offer no power fault protection(s).
I don't know if it does or not. I don't have a speaker hooked up to the motherboard or anything.

What brand of PSU would you recommend, by the way?
I've had no troubles with any of the Corsair TX or the HX lines of PSU's. They come with a 5 year warranty so that says alot about their reliability. The difference between the TX and HX is the HX is modular, meaning that the power cables hook up to the back of the PSU so you can use only the PWR cables that you require. - CORSAIR Enthusiast Series CMPSU-650TX 650W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC Compatible with Core i7 Power Supply - CORSAIR HX Series CMPSU-650HX 650W ATX12V v2.2 / EPS12V 2.91 SLI Ready 80 PLUS BRONZE Certified Modular Active PFC Power Supply
Note: The HX650w version does have the main 24pin motherboard PWR cord, but the others you can plug in the back.
Consider your self fortunate the 400W PSU has lasted a month and not done any damage to other hardware.
The 650W Corsair that Amd_Man linked to is the best bang for buck after the $30 rebate.
Aaaaaaa. Guess I'm gonna have to wait a while to get that replaced since I'm broke. D:
In the meantime, any other suggestions as to what might be causing this?
No that is the typical scenario when a PSU fails. They will usually power fans and and not anything else. To keep trying to start it up could possibly cause more harm to other hardware.
This is the PSU I got. - COOLMAX V-400 400W ATX v2.01 Power Supply

I had all of my other parts ready and I was really anxious to get it up and running, so I just went to a store and grabbed it. I suppose I should be more careful in the future when choosing my hardware. I'm gonna take it in with me today and test it with a multimeter.

I was following this thread and just noticed the coolmax PSU. I saw this review for one of their power supplies which is supposedly a 750 watt unit. During their testing, two of these units died on them when they were trying to pull 500 W out of it, let alone it's rated 750 w
They recorded a video of it happening in one of the review pages if you want to check it out.

Just to show how important it is to have a quality PSU for your precious components.
Good link Markgg88 and proves what we all say here about low quality PSU's. That 400w Coolmax is pure junk and I just hope it didn't take out other hardware. If your going to test your PSU then do it under load to get the real picture.
I tested the PSU and the multimeter was reading twice the voltage it was supposed to, the 12-volt rail was reading around 25 Volts. I think I should replace it. I just hope it didn't damage my mobo or anything else. D: But yeah, I've learned my lesson. Never buying from coolmax again.
That's not good at all. It's not just Coolmax, but any of the cheap generic PSU's that should be avoided. They offer no over current protection as you can now clearly see. The ones that I linked earlier have great protection against PWR problems and like I said, they have a 5 year warranty and that says it all.
The PSU is the very last item you should attempt to use anything less than top quality.
The other hardware is dependent on the PSU for a steady supply of clean sufficient power.
Hey, would you guys recommend this PSU? - Antec EarthWatts EA650 650W Continuous Power ATX12V Ver.2.2 / EPS12V version 2.91 SLI Certified CrossFire Ready 80 PLUS Certified Active PFC "compatible with Core i7/Core i5" Power Supply

A store near where I live carries this PSU but nothing by Corsair. I need my desktop back soon, but if you think I should wait a few days for a Corsair to come in the mail, I will.

EDIT: After reading some of the 1-egg reviews, I've decided to stick with the Corsair.
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