ASUS Sabertooth Z87 won't go to BIOS first time boot

[zjhoward]

First time post,

ASUS Sabertooth Z87
Intel i7-4770k
8 GB DDR3 G.Skill
EVGA GEForce GTX 750ti
Cool master v650
NZXT Case

The system doesn't boot, the cpu fan turns on and the green LED light at the bottom is lit, but besides that nothing else happens.

This build is for my friend, and I have a very similar one for myself so I have been comparing to it to try to figure out what is wrong. I tested the ram he has on my system and both of them worked.

In the MoBo manual it mentions that there are other LED lights around for POST that should light up when it's turned out, but these do not light up.

I've googled around and tried a bunch of things (removing the CD drive, SSD, and graphics card), but none of them have worked. Does anyone have a suggestion on a place to start?

Thanks for any help

 

[Ricofizz]

Check all the cables? You might've missed one

 

[Neur0nauT]

Are you getting any POST beep codes when you power the system on? Make sure your CPU is seated right and that the Heatsink is not clamped down too tightly. If the RAM is the same as your friend's and it works, then the CPU may be faulty/damaged, or else the mobo is faulty. Get ready to RMA stuff.

 

[zjhoward]

Check all the cables? You might've missed one

When you say check all the cables, the only thing connected to the MoBo (right now) is one stick of RAM, the processor, and the CPU fan (which spins fine). There aren't many cables to check there, and I believe the green LED at the bottom of the MoBo indicates that the PSU is hooked up to the MoBo correctly? Are there any other cables that I'm not thinking of that I should check?

@Neur0nauT
There is no beeping noise at all when it turns on. The CPU fan turns on, and that's it. No red LEDs come on (like they do on mine). I'll check that the CPU is set right, but we were very careful when putting it in.

Thank you for the suggestions. Anyone have any others?

 

[alexoiu]

Is there a case speaker connected to the motherboard? If yes, try starting the board with only CU and CPU fan installed (no memory). You should get 1 long 2 short beeps.

 

[Neur0nauT]

You should have these power cables going into your system from the PSU:

A 20/24 pin main ATX power cable into Mobo
A 4/8 pin 12v CPU plug into Mobo
5v System fan(s) connectors
6/8 pin PCIe connectors for your Graphics card
15 pin sata power going to your Hard drive(s)/Optical

4 pin connectors for any other peripheral things like front panels or fan controllers.

 

[zjhoward]

You should have these power cables going into your system from the PSU:

A 20/24 pin main ATX power cable into Mobo
A 4/8 pin 12v CPU plug into Mobo
5v System fan(s) connectors
6/8 pin PCIe connectors for your Graphics card
15 pin sata power going to your Hard drive(s)/Optical

4 pin connectors for any other peripheral things like front panels or fan controllers.

Thank you! I double checked all of these and now it boots to the BIOS. The problem was the 8 pin 12v CPU plug. Related to this, the PSU has 2 4 pin adapters, where the mother board has 1 8 pin slot. It's booting with only one 4 pin plug in, but is it recommended to use both 4 pin plugs? I can't find anything on it in the mother board manual

Thanks again for the help

 

[Neur0nauT]

You should have these power cables going into your system from the PSU:

A 20/24 pin main ATX power cable into Mobo
A 4/8 pin 12v CPU plug into Mobo
5v System fan(s) connectors
6/8 pin PCIe connectors for your Graphics card
15 pin sata power going to your Hard drive(s)/Optical

4 pin connectors for any other peripheral things like front panels or fan controllers.

Thank you! I double checked all of these and now it boots to the BIOS. The problem was the 8 pin 12v CPU plug. Related to this, the PSU has 2 4 pin adapters, where the mother board has 1 8 pin slot. It's booting with only one 4 pin plug in, but is it recommended to use both 4 pin plugs? I can't find anything on it in the mother board manual

Thanks again for the help

If your system runs on one 4 pin then thats fine. Most modern CPUs are low wattage. My i5 2500k is on 4 pins, and I overclock it sometimes too. If you find that it is powering down when under heavy load, then use the total 8 pins.

I'm glad you got it sorted. 😉