Several CPUs aren't connecting to LGA1700 boards.
Several CPUs aren't connecting to LGA1700 boards.
I’m looking for advice on this unusual hardware situation. You’ve already ruled out many obvious causes—power supply, cables, BIOS updates—and your testing shows multiple CPUs failing to power up. The readings you’ve taken suggest serious issues either with the boards or their connections.
It seems the boards themselves might be compromised. The PSU shutting down immediately on i7-12700K and the near-instant power cut on i3-12100 point toward a hardware fault in the board rather than just a transient issue. Even though you checked the sockets, no visible damage was found, but the internal signals don’t look right.
With the i7 working before and now failing, it’s likely one or more boards are defective. The 0.3 V Vcore reading and the red CPU LED indicate voltage instability, which could be a sign of a failing regulator or capacitor. Measuring the actual voltage across the VRMs and comparing to specs would help confirm.
When you get the Celeron, focus on these steps:
- Check for any visible signs of burn marks or swollen capacitors on the boards.
- Test each board individually with a known-good PSU and monitor voltages.
- Look for consistent POST behavior—if one board works but others don’t, it’s likely a board issue.
- Consider running diagnostics like SMART or thermal imaging to spot hidden faults.
This pattern suggests either multiple dead CPUs or a batch of faulty boards. Be cautious about assuming random failure unless you confirm hardware integrity.
If the Celeron displays the same 0.3 V shutdown pattern, it suggests problems with the boards or VRMs. Verify BIOS versions, as outdated firmware may prevent newer CPUs from initializing properly. Clear CMOS during transitions and use only one RAM stick plus the onboard GPU with the G6900. If both systems respond identically even with the G6900, consider a power supply issue or hidden socket/VRM damage. Beginning with a reliable low-cost CPU is the best strategy.
I'm frustrated because the I3 should have been my reliable CPU already. I checked the VRMs on the unknown board to see if any could handle 12V, but nothing came up. It makes me think maybe this board is prone to damaging any CPU it receives. I've tested the PSU on another system (I7 7700) and it worked fine.
The seller might be open to testing additional CPUs if you bring them. Also, it wasn't a typical reseller store—it seemed like a personal seller offering second-hand items.
I purchased it from an eBay business account and reached out to the seller for clarification. I believe he might be selling in bulk without proper testing, so I’ll keep an eye on things. As I mentioned, I ordered a Celeron model—the most affordable option for that socket—to get a reliable baseline. I plan to test this known good board first; if it works, I’ll move to the new “dodgy” one only if necessary. We’ll be more informed then. I dislike having to follow this process, but I don’t have clear guidance on how to properly assess a CPU’s condition or identify damage. My multimeter is handy, and I have some basic electronics knowledge, though the motherboard itself is quite complex. I’ve only found advice suggesting checking for 12V before installing the CPU, just to prevent damage—though it seems risky.
The main way to check CPUs is using a reliable motherboard. Since a motherboard is quite intricate with many components that might fail, it’s important to test properly. Many old CPUs are still available, while modern motherboards are rarer. Because certain parts in a motherboard are likely to fail over time, troubleshooting a CPU requires specialized tools like a development board. These offer precise measurement options but are expensive and require customization.