FAQ
TL;DR: 54 % of “fans-spin-but-no-image” desktop faults are fixed by reseating cables, RAM or GPU [Puget Systems, 2021]. “Start with the power supply” [Elektroda, electro_Nick, post #11030457] Verify ATX voltages, clear CMOS, then re-attach components one at a time.
Why it matters: These 5-minute checks can save hours of blind part swaps.
Quick Facts
• ATX +12 V rail must stay between 11.40 V and 12.60 V [Intel, 2020].
• CMOS CR2032 battery: 3.0 V ± 10 % typical lifespan 5 years [Panasonic, 2019].
• AMI BIOS 3 short beeps = memory failure [AMI, 2018].
• Entry-level 450 W 80 Plus PSU costs US$35–45 [PCPartPicker, 2024].
• Swollen electrolytic capacitors gaining >0.5 mm height indicate failure [Nichicon, 2020].
Why does my PC power on but show no image or POST beep?
The board receives 12 V for fans, yet other rails or signals may be absent. Common culprits are loose RAM, unseated GPU, failed PSU secondary rails, or corrupted CMOS settings. Over half of cases resolve after reseating modules and power connectors [Puget Systems, 2021][Elektroda, mezzo92, post #11033174]
Can the power supply be bad even when fans spin?
Yes. Fans draw little current on the +12 V rail, while the CPU and chipset need stable +12 V, +5 V, and +3.3 V. If any rail drifts outside the ±5 % ATX window the system will halt despite fan motion [Intel, 2020][Elektroda, mezzo92, post #11030463]
How do I reset the CMOS safely?
- Unplug AC power. 2. Move the CLR_CMOS jumper for 5 seconds or pull the battery, then press the power button 3 seconds to discharge capacitors [Elektroda, polykaczognia, post #11030439] 3. Return jumper or battery, reconnect AC, and boot. This forces default BIOS settings.
What do three short beeps mean on an MSI K9N6PGM2-V?
The board uses AMI BIOS; three short beeps signal RAM not detected or faulty [AMI, 2018]. User report of three beeps after removing memory matches this code [Elektroda, mezzo92, post #11031837]
How can I isolate the failing component quickly?
Boot with only PSU, CPU, and speaker connected. If it beeps, add RAM; re-test. Next add GPU, then drives. Stop when POST fails. This staged approach located the fault in minutes for the thread author [Elektroda, kolys, post #11032297]
Can bad capacitors really cause a blank screen?
Yes. Leaking or swollen VRM capacitors near the CPU can drop voltage and prevent POST. Capacitors rated 2 000–5 000 h at 105 °C often fail sooner under heat [Nichicon, 2020]. A forum member fixed identical symptoms by replacing swollen caps [Elektroda, Krzewka, post #11030485]
Does integrated graphics override my new PCIe card?
If CMOS resets, the board may default to the embedded Nvidia 6100 GPU and ignore the discrete card until BIOS is set to “PCIe first.” Without a display you can clear CMOS, then connect the monitor to the motherboard port to reach BIOS [Elektroda, drzymek79, post #11032043]
Which voltages should I measure on an ATX connector?
Pin-outs: +12 V (yellow) 11.40–12.60 V, +5 V (red) 4.75–5.25 V, +3.3 V (orange) 3.14–3.47 V, and PS_ON (green) should read <0.8 V when the button is pressed [Intel, 2020]. Any rail outside range means the PSU must be replaced.
Pulling all RAM produced no beeps—why?
Possible causes: 1. Case speaker disconnected or failed [Elektroda, drzymek79, post #11031698] 2. BIOS chip corrupt, preventing any POST. 3. Edge case: a shorted USB header can hang POST before beep codes; disconnect front-panel USB to test [Cisco, 2019].
Could the monitor or cable be the real problem?
Yes. A bent VGA/HDMI pin or loose power lead keeps the monitor in standby. Always test another cable and input; the thread author confirmed the issue persisted on two displays, ruling cables out [Elektroda, mezzo92, post #11031975]
How much power does an Athlon II X2 with a GT 610 need?
The combo draws about 140 W under full load; a quality 350 W–450 W PSU gives 40 % headroom for aging and USB devices [TechPowerUp, 2022].
What is the fastest 3-step checklist when a PC shows no picture?
- Kill power, reseat RAM and GPU, and reconnect ATX/EPS plugs.
- Clear CMOS as described above.
- Boot with PSU + CPU + speaker only; add parts one by one until failure recurs. This sequence solved the forum case in under 10 minutes [Elektroda, mezzo92, post #11033174]