I have this strange problem. Sometimes when I turn on the computer or reset, the BIOS hangs with debug code 4f (which is labeled in the manual as reserved). It doesn't beep or post, and the usb ports stay off without power. If I press the reset button once or twice it works fine.
I have tested by removing the gfx Zotac-gtx-960 card and it seems to post every time (it could be false positive not sure) but it seems the post is faster.
I have updated the BIOS to F10b to see if it gets fixed, corrected the ram layout (it seems the motherboard labels for ram are wrong) and also disabled the onboard card from bios. It seems like the problem improved but still happens.
The CPU was not originally supported by this motherboard, but now it is, after F9.
The PSU supports Haswell refresh power preservation feature.
The 6 pin connector is connected correctly to the video card, the video card is set in the right slot (I checked the manual). When it posts, the PC works fine no problem. I have checked the ram with memtest (no errors), the video card seems functional, I played MGS and it works fine with no issue.
- Anyone experienced similar issue?
- Is it possible that there is a problem with the graphic card that makes it not work at first sometimes but when it does everything is ok?
- Is it possible for instance that the problem is the thermal paste under the CPU? Taking into account that things work perfectly after post, and that removing the GFX card seems to make it work with no problem?
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Hardware specs:
ga-z87x-ud3h F10b bios
Core i5-4960k (supported from F9 bios)
DDR3 PC3-12800 CFD-W3U1600HQ-4 4gb x 2
ZOTAC GeForce GTX 960 ZTGTX96-2GD5MGS01
PSU: FSP AURUM92+ 650w
Edit
It seems likely the video card. I sent it for repair. When placed in the PCIe x16 it caused the symptoms above, but in the x8 worked fine. When it comes back, I'll try it again in the x16 and post an answer if it is the reason or edit if it is not.