A few $60 motherboards

[Rajahal]

Sorry, I didn't feel like making a separate post for each one.

 

MSI 870-G45 AM3 AMD 870 ATX AMD Motherboard

Upsides: 2 PCIe x16 slots, 1 PCIe x1 slot, 6 onboard SATA, potential for 24 drive support

Downsides: no onboard video, full ATX size

$59.99 + free shipping after promo code EMCYWYP33 (expires 8/9/2010)

 

BIOSTAR TA790GXB3 AM3 AMD 790GX ATX AMD Motherboard

Upsides: 2 PCIe x1 slots, 6 onboard SATA, onboard video, potential for 18 drives

Downsides: only 1 PCIe x16, full ATX size

$59.99 + free shipping after promo code EMCYWYP34 (expires 8/9/2010)

$49.99 after $10 MIR

 

BIOSTAR TH55B HD LGA 1156 Intel H55 HDMI Micro ATX Intel Motherboard

Upsides: 6 onboard SATA, microATX size, onboard video (included in i3 CPU)

Downsides: only 1 each PCIe x16 and PCIe x1 slots, potential for 16 drives

$59.99 after $10 MIR

 

Pair the first two with the Sempron 140 CPU for a low power server.  The last one would pair well with an i3 CPU for a lower power yet powerful server.