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Very Old mobo + Old CPU dilema

5 posts · originally from https://geek.digit.in/community/threads/very-old-mobo-old-cpu-dilema.149263/

U
Ultra_Bloodshed Original post #1
Nov 26, 2011 at 6:22 PM
My friends are throwing away their old stuff so I thought I'd gather those parts and assemble a system for casual stuff. This are the mobo and CPU I gathered.

MOBO: ASUS M2N-MX SE
CPU: AMD Phenom II X3 720


The Asus board is based on the AM2 socket. The CPU is AM2+ or AM3 socket based, I am a bit confused. As far as I know, AM2+ and AM2 are backward compatible.

But after assembly, the system fails to boot up. On power on, the CPU fan rotates for 2 secs and shuts down. I am guessing it's "rejecting" the CPU.

What am I doing wrong? Are they incompatible? Do I need to update the bios in the mobo? If so, how do I update something that won't boot!
coderunknown
Nov 26, 2011 at 6:41 PM
it won't support any AM3 processor.
U
Nov 26, 2011 at 6:50 PM
Ummm... why not? All AM3 CPU are backwards compatible with AM2/AM2+ sockets.
coderunknown
Nov 26, 2011 at 6:59 PM
nope. AM3 cpu are backward compitable with AM2+ socket, not AM2 socket. and that board have AM2 socket & so will support maximum of AM2+ only.
topgear
topgear #5
Nov 27, 2011 at 4:22 AM
@ OP - here's the cpu support list page of the mobo ;-)
ASUSTeK Computer Inc. - Motherboards- ASUS M2N-MX SE