need some cpu diagnostic help

[Sniping]

i made this thread a few weeks ago about how my old computer's (lets call it computer A) cpu crapped out. i ended up finding another replacement cpu for it. this new cpu works fine in my other computer (computer B), but doesn't post at all in computer A. i dropped the cpu from computer B into computer A and it booted just fine, but nothing with this new cpu i just bought. they're all 6th gen cpu's and there's no chipset incompatibility or anything like that. tried clearing the cmos but i don't think that's the problem, and didn't do anything. i'm stumped now, what gives here?

[tp4tissue]

could be a dud,  check the base pads, see if there's anything odd.

[Sniping]

could be a dud,  check the base pads, see if there's anything odd.

but it works fine in my other computer...how does that even happen?

[tp4tissue]

try flashing a different bios. prolly some microcode incompat, and swap the ram.

There should be post codes though, the beep-boop.

[Sniping]

try flashing a different bios. prolly some microcode incompat, and swap the ram.

There should be post codes though, the beep-boop.

i'll try the bios flash and ram swap. the motherboard hasn't been making any of those beeps though, do they all do that? it's definitely cpu related somehow so i feel like those pre boot beeps wouldn't be helpful.

[Rika]

Is your mobo running latest bios, if it's a ryzen chip there's a decent amount of boards that might not support certain chips without a new version or may even LOSE support if it's an older chip, honestly you haven't given a crazy amount to go off of

Sent from my SM-N976B using Tapatalk

[Leslieann]

I'd bet it's a bios issue causing A not to work in B.

Bit of a warning...
There's a reason old boards cost what they do, they are far more likely to fail than a CPU which are extremely durable. If a CPU works in any other board, I would put aim at the board every time. A dying cap, flakey ram, buggy bios, there is just much more to go wrong on a board.  I've been doing this quite a long time but I can still count the number of bad CPUs I've seen on one hand, the number of boards however is off the charts.

[yui]

apart from failed overclocking and old FX CPUs (not dead yet but both mine now need over-voltage to be stable at base frequency...) i never had a cpu die on me without the motherboard being the culprit, to me, although you did not say what your old and new CPUs are, it may be that the vrm are failing, so a lower power CPU will be able to start but the motherboard may not be able to supply enough power for the higher power ones, although recapping old socket 7 motherboard is easy, newer stuff maybe not as easy (with all those pesky smd components)

[suicidal_orange]

Does original/assumed dead CPU A also work in computer B?

[tp4tissue]

Does original/assumed dead CPU A also work in computer B?

Also, Cpu B in Board A, it boots, but was it tested with any apps.

[Sniping]

bios flash did it. forgot the new cpu was actually 7th gen...and i never flashed the bios on the old computer. took a minute to figure this one out though. cheers yall

[Leslieann]

Awesome! Glad you got it running.

[suicidal_orange]

So further diagnostics required - any burnt caps on the dead CPU?  Is it delidable or soldered IHS?  Was it abused with voltage so not a surprising failure?

My only dead CPU has a cracked die which (assumedly) led to a burnt cap.

[tp4tissue]

[Sniping]

spoke too soon...it's crashing as windows loads in every time. i gotta take another look at this 

[Darthbaggins]

What's the error on windows crash - if it gives a code error.  Also could be a memory issue as well - just to add more to the pile.

[yui]

spoke too soon...it's crashing as windows loads in every time. i gotta take another look at this 

to be honest i would suspect 2 things, windows got corrupted and fails to boot or overclock instabilities. although i have 2 cpus that displays instabilities when used at stock voltage and clocks but will be stable under overvoltage, but both got very heavily overclocked with insufficient cooling for years. other than that i still suspect your motherboard vrm of being unstable...
one easy thing to try is to get a boot usb and try that, if it boots it likely is windows corruption, if it also crashes it, to me, screams unstable voltages so either motherboard or power supply (if the 12v crashes on load your cpu voltage will also crash and so will in turn the whole system)

[tp4tissue]

Return it,  wait for Zen 3 .. 5950x