The K7S5A is highly acclaimed for its ultra low price and ability (albeit with an unofficial BIOS) to support FSB adjustments and all the new CPUs, despite being so old. Furthermore, its performance is not too shabby. LONG ago, I bought a KT7E... I'm actually typing on this PC right now.
It used to have a duron 600 overclocked to 1 ghz. So here's the situation.
On my school PC (8K5A2+), I used to have an old Athlon XP 1700 (the first stepping, palomino, etc). My roommate had a Micron PC w/ a 1.4 ghz Athlon (t-bird). I bought a TbredB 1700 and gave him my old CPU, citing that the 66 mhz more increase and the Athlon XP enhancements would make it a painless, and MAYBE noticeably faster, upgrade. I asked for the previous 1.4 ghz T-bird in exchange.
So i'm happy as for $50, I got my computer up to 10x200. He's happy as his Micron PC looks the same and feels the same but his dorky roommate (AKA me) claims that it now has funny things like data prefetch and a little more clockspeed. I just got happier about my $50 purchase though.
I came home, swapped out the duron 600 out of my KT7E. I popped in the 1.4 ghz t-bird and it worked after a BIOS update. It's right now running at 1.6 ghz!

. I'm sure it could still go a bit higher too! I recently upgraded to 512mb memory (only PC133, but fast timings).
All i'm saying is that i'm quite happy with this motherboard. I'm getting very solid performance (for web browsing, word processing, and minimal gaming) out of a motherboard that came out in late 2000! Enough of my rambling.... I'm going to try and o/c a bit higher. Heat isn't a problem as this is in my dual heatercore machine

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-Kev