Turns on but no post

realdrx

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Jul 14, 2010
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Just put this together
Intel Core i7-860 Lynnfield

CORSAIR CMPSU-850TX 850W

ASUS P7P55D-E Pro LGA 1156

EVGA 012-P3-1470-AR GeForce GTX 470

2 CORSAIR XMS3 4GB (2 x 2GB) 240-Pin DDR3

Western Digital Caviar Black WD2001FASS 2TB

COOLER MASTER HAF 932 AMD Limited Edition

At first it posted fine I was in bios looking around then it restarted and kept restarting turned it of at the psu. Now it turns on but doesn't post and no trouble shooting beeps.
I went thought the trouble shooting sticky. Disconnected every thing ecpt hsk and cpu still no beeps. The cpu led is red and blinking. I noticed that my front fan was half turning stopping half turn stop. So I disconnected it from the mobo and put direct to psu and works fine. Bad mobo?
 
Solution
You have worked through our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems
yes? I mean work through, not just read over it. You worked through the breadboarding section?

Breadboard - that will isolate any kind of case problem.
http://www.tomshardware.com/forum/262730-31-breadboarding

The breadboarding thread has a paragraph about how to build and test a PC in stages.

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU. You do have a case speaker installed, right? If not, you really, really need one. If your case or motherboard didn't come with a system speaker, you can buy one here:
http://www.cwc-group.com/casp.html

You can turn on the PC by...

cpatel1987

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Feb 2, 2010
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Did it post when you put the heatsink directly to the PSU? If not, then according to http://www.fonerbooks.com/cpu_ram.htm, your mobo is bad.
 
You have worked through our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems
yes? I mean work through, not just read over it. You worked through the breadboarding section?

Breadboard - that will isolate any kind of case problem.
http://www.tomshardware.com/forum/262730-31-breadboarding

The breadboarding thread has a paragraph about how to build and test a PC in stages.

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU. You do have a case speaker installed, right? If not, you really, really need one. If your case or motherboard didn't come with a system speaker, you can buy one here:
http://www.cwc-group.com/casp.html

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.

At this point, you can sort of check the PSU. Try to borrow a known good PSU. 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.
http://www.youtube.com/watch?v=5FWXgQSokF4&feature=youtube_gdata

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.

cpatel, what on earth are you talking about? "Did it post when you put the heatsink directly to the PSU?"

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 or long single beeps indicate a problem with the memory.

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.

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.
 
Solution

realdrx

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Thanks for help but I figured out it was the psu. Yes I worked thought it. I didn't have a different PSU to try so I brought it back into micro center and we work thought the parts. Installing win 7 right now. I don't know if this is true but the guy at micro center said that the blinking CPU led indicates faulty psu.