Question No display or beeps after doing some maintenance, not sure what to try next ?

[Jasperstarr46]

In 2017 I installed an i7-7700K on an ASRock Z270 Extreme 4 mobo with CM (Cooler Master) Hyper 212 Evo HSF, CM G750M PSU, 2 16G sticks of DDR4 RAM, an EVGA GTX 1070, 512G Intel NVMe SSD in an M.2 slot, a 2T HDD, and an optical drive. Oh, I also installed an 802.11ac WiFi/BT card in the appropriate M.2 slot, but never really did get those ridiculous pigtail connectors properly attached and gave up in my eagerness to get on with the installation of Windows 10 and using my new rig.

It's served me well for 6 years, but was due for some maintenance, so I:
-- R & R ed the HSF to renew the thermal paste. Ditto the GPU.
-- Once again attempted to connect the accursed pigtails to the WiFi card, and did get the main connected. (Having WiFi on my PC is becoming more important as I may opt for 5G internet service soon and the router will not be near my PC.)
-- The optical drive tray wouldn't eject so I wanted to service the drive belt.

Once I finished all of that, I decided to start it up and check everything before I put the panels back on the case, but... it didn't start. The fans (case, HSF, GPU, PSU) would start briefly, then stop. Start briefly, then stop. And that cycle would continue until I switched off the PSU. I spent the rest of the day removing parts one at a time and retesting. At some point I remembered I have a speaker and connected it, but it was not helpful. It may have produced a barely audible beep when the fans started up.

The next morning I cleared CMOS and the symptoms changed. It acts like it is running but it displays nothing; the fans start and continue running except the GPU (it starts but quits), presumably because it's vacationing. I have connected to 2 different devices using the mobo's VGA and HDMI ports, I've tried the GPU's HDMI port, I've tried to catch BIOS on all 3, nothing is displayed. Both monitors and their cabling are known good, I hooked up my old laptop to them today to verify. Even though the CMOS battery still tested at 3.12V, I changed it, too. And removed and swapped around parts.

FWIW, this board has 2 BIOS chips marked P1.20, each with an led next to it. When I apply power, the led by the primary BIOS chip lights up and remains lit until after I switch off the power supply.

In any case, I have no display and no beeps unless I remove something critical like RAM. I really don't know what to do at this point, other than to start taking parts out of the case and trying the breadboard thing. That, and maybe taking a meter to the power supply.

If anyone can offer any other ideas, I'd be grateful. This has been a nightmare.

 

[Jason-Julius]

Hello! I hope you are well, If you are facing this problem you need to check all connections and reseat components, try breadboarding outside the case with essential elements (CPU, 1 RAM stick, GPU), test with a different PSU if possible, test GPU in another system or use onboard graphics, ensure secure display cable connections, try different GPU display outputs (HDMI, DVI, DisplayPort). check the motherboard manual for BIOS recovery instructions, test with known working RAM if available, and reset BIOS settings to default.
Hopefully, your issue will be resolved.
Thank-you.

 

[Jasperstarr46]

Update: I seem to have isolated the problem and it's a doozy. Two of the DIMM slots on the mobo are fubar. I discovered this by trying a single stick in each slot, one at a time, and suddenly had a display. I have since reinstalled the (boot) SSD and it is loading Windows.

So I will continue to add back components. I think most of it will survive albeit in a different form. Meanwhile, I'll have a system to use while I shop for a new mobo and Win 11 ready CPU.

Thank you for your thoughtful suggestions and encouragement, Jason-Julius. I really appreciate it.

 

[CountMike]

Update: I seem to have isolated the problem and it's a doozy. Two of the DIMM slots on the mobo are fubar. I discovered this by trying a single stick in each slot, one at a time, and suddenly had a display. I have since reinstalled the (boot) SSD and it is loading Windows.

So I will continue to add back components. I think most of it will survive albeit in a different form. Meanwhile, I'll have a system to use while I shop for a new mobo and Win 11 ready CPU.

Thank you for your thoughtful suggestions and encouragement, Jason-Julius. I really appreciate it.

Recheck CPU socket, bent or damaged pins not making good contact are often cause of RAM slot malfunctions,

 

[Jason-Julius]

Update: I seem to have isolated the problem and it's a doozy. Two of the DIMM slots on the mobo are fubar. I discovered this by trying a single stick in each slot, one at a time, and suddenly had a display. I have since reinstalled the (boot) SSD and it is loading Windows.

So I will continue to add back components. I think most of it will survive albeit in a different form. Meanwhile, I'll have a system to use while I shop for a new mobo and Win 11 ready CPU.

Thank you for your thoughtful suggestions and encouragement, Jason-Julius. I really appreciate it.

No need to thank-you Jasperstarr if you have any queries you can ask me any-time Thank-you.