That's an interesting tip. I googled this and found the following about M57SLI, the board: "Most AM2 Motherboards Not Phenom Ready... we weren't able to run it [Gigabyte GA-M57SLI-S4] with the Phenom processor - despite official BIOS support. The pre-production motherboard revision 0.2 could be the issue, though."
I'm not sure what version my board is, but either way it seems quite iffy whether it supports newer CPUs or not.
A pre-production board can behave differently. Official bios F13 adds AM2+ Phenom support and F14 AM2+ Phenom X3 support.
Just checked: newegg
has a refurbished AM2 X4000+ for $35 including shipping. AM2 not AM2+ should be no problem it was supported in all bios versions. Add two sticks 2GB DDR2 $25 each and you're done, all for $85.
Thanks. The Sempron 3400+ is playing video at less than 5 fps. In the following benchmark, an Athlon X2 4200+ is maybe 30% faster than a Sempron 3400+: http://www.phoronix.com/scan.php?page=a ... =483&num=5
So, I'm not sure the Athlon 64 X2 4000+ will be fast enough.
But I'm reading the motherboard info on Gigabyte's site: Support for Socket AM3/AM2+/ AM2 processors: AMD Phenom™FX processor/ AMD Phenom™ processor/ AMD Athlon™ 64 FX processor/AMD Athlon™ 64 X2 Dual-Core processor/AMD Athlon™ 64 processor/AMD Sempron™ processor.
Still, questions on my mind are, is it safe to ignore reports about the pre-production BIOS regarding "not Phenom ready", and which compatible processors may be fast enough, if any.