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New Build Won't POST, Power Fluctuating BIOS freezing

Last response: in Systems
January 14, 2011 8:13:43 PM

I have a brand new self built computer that will not run stable during the initial boot into Bios. It freezes when it loads into the initial BIOS screen and other times it will continuously restart when it attempts to load the BIOS screen.

The computer has never ran stable yet. I have read through your previous post about what to check for before posting a new thread.

So this is a new build for a friend of mine. Here is a list of the parts I am using to create the machine:

Cooler Master CM 690 Advanced II Case
GIGABYTE 790 FXTA-UD5 Motherboard
ThermalTake TR2 RX 1200W PSU
AMD 1090T Processor
Cooler Master V8 Heatsink
G Skill Ripjaws DDR3 240-pin 8GB (4gb x 2) 1600 MHz ( PC3-12800 ) Memory
Kingston Solid State Hard Drive 128gb
Radeon 4970 X2 Video Card PCI-E - 1
Radeon 4970 X2 Video Card PCI-E - 2 (Just so your all aware, I attempted to run without both video cards connected and the same issue exists)
KILLER 2100 Network Card
LITEON 24X DVD-RW Sata Drive
Cables Unlimitied 3.5" Memory Card Reader

So I built the entire machine and followed every step in the Motherboard manual. All the connections are legit, they have been checked about 10 times. Initially I had all the parts listed above installed and I tried to turn on the machine. The first thing I noticed was the fluctuation in power on all the parts.Silent at first then vvvrrrrRRROOOOMMMmmmm Up and down up and down then stable. THen BEEEP. Nice basic loud beep but no video whatsoever.

So since I had no video I pulled out the KILLER 2100 Network Card to start testing parts. Turned power on and again Power Fluctuation Up and Down, Up and Down, Fast spin, slow spin, then quiet and stable and my basic BEEP. After the beep to my amazement I had VIDEO! Horay!. Then it loads the BIOS next, a big colorful Gigabyte Bios screen pops up and boom it crashes and restarts. It then proceeded to load the initial bios screen again but to no avail it still crashed and restarted upon loading the bios screen. So I pulled one of the video cards out and only ran one card. Upon turning it on the machine still did the weird power fluctuation and the same failure occurred when the bios screen loaded.

So I removed the 4870 and tried a different video card entirely (Geforce 460). Turned it on and no crazy power fluctuations this time, it loaded to the bios screen, and oddly enough it let me actually go into bios and look around. But upon exiting bios, boom, it crashed. (No i did not change any settings whatsoever while I was in BIOS).

After that failure I tried a different solid state hard drive (w/ geforce 460), I took out the Kingston and put in a Super Talent 64gb, No power fluctuation, but Bios still crashes and I'd like to mention that sometimes it lets me into the real bios options and sometimes it does not. So after all that swapping and changing of parts I took out one of the RAM Sticks. Turns on and a super long beep goes off. No bios No nothing. So after that I put my other stick back in and I currently have it down to the CPU, RAM, VIDEO CARD and a HDD only. Those are literally the only parts connected and it still fails. I don't know what the issue is except the memory, and here is why I believe that is the issue.

When i Installed the geforce 460 and it let me go into the actual Bios Screen I was inside the DRAM Timing Information and it showed the speed of the Memory. I was just sitting there staring at all the options and I saw the Memory Speed change back and forth, very rapidly from 400Mhz to 800Mhz in an extremely glitchy fashion, you could tell what it was doing was not normal. Reminded me of when nintendo games would fail, Big Blocks on the numbers and what not. Glitchy for sure.

Something else worth mentioning: When it freezes and you hold in the power button to shut it off, all the lights inside the case on the various equipment fade off, not shut off instantly.

Questions we need answered:

So my first question is why does the bios freeze and fail?

Second question is what are the power fluctuations all about when I have the 4870s installed (Having one 4870 installed also causes power fluctuations)?

and finally the other question is "Would in-compatible RAM make these issues im having exist in a new build?"

I'm in your hands now, I really don't know where to go from here to be honest with you guys. I have 14 years experience with computers. An associates degree in Computer Science and I have built a few PCs for friends in the past with no issue. I will be forever grateful if I could have some help on this. You can be as technical as you like with your responses and I will be able to decipher what you mean and try out your methods.

Thank you.

January 14, 2011 9:47:30 PM

Have you tried it with just one video card (check each individually in first PCI-e slot) installed? (Do you have required aux gpu power input or inputs connected?)

Disconnect all drive molex/sata power inputs, etc....

Drop to a single stick of mem in required slot....

If this is a new build, you might want to check case/mb standoff locations precisely match your MB's standoff holes...potentially disastrous to short a MB out this way....

It seems illogical for a 1200 watt PSU to not handle it, but, any PSU can fail...
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January 14, 2011 9:56:57 PM

mdd1963 said:
Have you tried it with just one video card (check each individually in first PCI-e slot) installed? (Do you have required aux gpu power input or inputs connected?)

Disconnect all drive molex/sata power inputs, etc....

Drop to a single stick of mem in required slot....

If this is a new build, you might want to check case/mb standoff locations precisely match your MB's standoff holes...potentially disastrous to short a MB out this way....

It seems illogical for a 1200 watt PSU to not handle it, but, any PSU can fail...

Yes, I tried one 4870, no success, one Geforce 460 no success and two 4870s no success. In addition to that, I've tried 1 stick of RAM (Long BEEP only) No Bios, No Video. I have check motherboard standoffs, they are matched up perfectly. Also disconnected all drives and literally only had cpu, ram, hdd, and video card connected. No success.
January 14, 2011 9:58:53 PM

OgCracKer said:
I'm thinking with power fluctuations through out the system would lean more towards a PSU issue. If you have an extra PSU laying around, try that.

And here's a real good guide for troubleshooting.

I have read through the troubleshooting guide before I posted, thank you for that though. It is very helpful. On another note I do have another identical power supply that I will try. Its for another build im doing but I will test it and see if this is the fix. Thank you.

Best solution

January 14, 2011 11:13:15 PM

Try the following. It's an expansion of the troubleshooting steps in my breadboarding thread listed in the "won't boot" guide.

I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different, but they all use a single short beep for a successful POST.

Breadboard - that will help isolate any kind of case problem you might have.

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.

Make sure you plug the CPU power cable in. The system will not boot without it.

I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.

You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.

If no beeps:
Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.

At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.

A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.

This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

If the system beeps:
If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.

Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.

Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST.
At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.

Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
January 22, 2011 12:26:59 AM

Best answer selected by RyanRusty29.
January 22, 2011 6:17:21 AM

This topic has been closed by Maziar