View Single Post
Old 06-17-2018, 03:01 PM   #31
momaka
Badcaps Veteran
 
momaka's Avatar
 
Join Date: May 2008
City & State: VA (NoVA)
My Country: U.S.A.
Line Voltage: 120 VAC, 60 Hz
I'm a: Hobbyist Tech
Posts: 8,504
Default Re: ASUS A7M266 Kills T-Bred B??

I've personally never had and never seen a CPU burn out (or burn out the VRM) due to the board not supporting it. That is, as long as the CPU is socket and pin signal -compatible with the board, nothing should burn.

Most VRM controllers have only so many valid V_core voltage states, so at worst, the CPU will select an either an invalid (VRM controller shuts down) or an incompatible voltage (but nothing damaging to the CPU, as VRM controllers are regularly capped at a certain max voltage.) From my experiments, this has always just resulted in no POST, but nothing else. Perhaps for very very old boards (Pentium II or earlier??), this might not be true. But anything Athlon/Athlon XP and Pentium 4 is relatively new in terms of VRM design, and thus fairly protected.

As my most recent example, I put a s775 Pentium 4 CPU into a Intel mobo that only takes C2D/C2Q/PDC CPUs. Did this to test the VRM after a repair (it kept blowing FETs with known compatible CPUs, so I didn't want to risk burning my C2D chips anymore). The V_core with the Pentium 4 CPU was incorrect (1.1V instead of 1.4V), and as expected, the board did not post. But I left it running for a good 20 minutes to see if the VRM would blow a FET again. It didn't. Then I stuck a C2D chip and tested the board again. All was well afterwards. FETs kept blowing because one of the phase drivers was bad, which I changed before testing this last time before trying the P4 CPU.

Last edited by momaka; 06-17-2018 at 03:02 PM..
momaka is offline   Reply With Quote