Socket 939 costs a little bit more than socket 754 motherboards but it support all Amd CPUs. So you can build a medium cpu Htpc today and you can upgrade your CPU in the future if you want to make it a high end htpc for games or other applications. Also Athlon64 cpus consume much less power than the P4 Prescott. For example a P4 660 system with a vga card like Radeon X800, requires about 120W when it's idle and 230W with full CPU and graphics load. On the other hand an Athlon 4000+ needs only 100W when it's idle and 160W with full cpu & graphics load. So, for high end Htpcs we recommend a 939 motherboard.

  We chose three motherboards for HTPCs.



I) GIGABYTE GA-K8N51-PVMT-9



Form factor: MicroATX 24.4 x 24.4 cm.
CPU socket: Socket 939.
Supported processors: AMD Athlon64 X2/ 64 FX/ 64.
Chipset: NVIDIA nForce 430.
Communication Ports: 1 x PCI-Express X16, 1 x PCI-Express X1, 2 x PCI, PS/2 Keyboard/ Mouse, 1 x S-Video (TV- out), 1 x VGA, 1 x LPT(parallel), 4 x USB 2.0/1.1 (+4 added external), 1 x RJ45(LAN), 1 x IEEE1394 (Firewire), Audio (4 x Line-out/ 1 x Line-in/ 1 x MIC).
Hard disk support: 4 X Serial ATA 3Gb/s, RAID 0,1,0+1,5, 2 x UDMA ATA 133/100/66 up to 4 IDE devices.
RAM Sockets: 4 Dual channel DDR400/333/266 up to 4GB.
Additional characteristics: Realtek ALC880 Audio Codec, onboard vga NVIDIA GeForce 6150, CICADA VSC 8201 Gigabit LAN PHY.
BIOS: 4M bit flash ROM, Award BIOS.


II) GIGABYTE GA-K8N51-GMF-9



Form factor: Micro ATX 24.4 x 24.4 cm.
CPU socket: Socket 939.
Supported processors: AMD Athlon64 X2/ 64 FX/ 64.
Chipset: NVIDIA nForce 430, Super I/O: Winbond W83627 chip, CICADA VSC 8201.
Communication ports: 1 x PCI-Express X16, 1 x PCI-Express X1, 2 x PCI (PCI 2.3), 2 x PS/2 Keyboard/ Mouse, 1 x VGA, 1 x LPT, 4 x USB 2.0/1.1 (+4 externally), 1 x RJ45, 1 x IEEE1394, Audio (4 x Line-out/ 1 x Line-in/ 1 x MIC), S/P DIF in/out, 1 x COM.
Hard disk support: 4 X Serial ATA 3Gb/s (RAID 0,1,0+1,5), 2 x UDMA ATA 133/100/66 IDE (4 devices IDE).
RAM Sockets: 4 sockets for DDR 400/333/266 184 pin up to 4GB. Dual channel support.
Additional characteristics: Realtek ALC880 Audio Codec, Gigabit LAN PHY chip, onboard vga NVIDIA GeForce 6100 and onboard IEEE1394 controller VIA VT 6307 IEEE1394.
BIOS: 4M bit flash ROM, Award BIOS.


III) ASROCK 939S56-M



From factor: MicroATX 244mm x 224mm.
CPU socket: Socket 939.
Supported processors: AMD Athlon 64X2, Athlon 64FX, Athlon 64.
FSB speed: 1000 MHz.
Chipset:
- Northbridge: SiS 756
- Southbridge: SiS 965L
Communication Ports: 1 x PCI Express x16, 1 x PCI Express x1, 2 x PCI, 4 USB 2.0 ports (+4 externally), 1 x RJ45 LAN port, 1 x Serial (COM1), 1 x PS2 Keyboard, 1 x PS2 Mouse, 1 x Parallel (LPT1), 2 x Audio (Line In/Out, Mic In).
Hard disk support: 2 x ATA 133/100/66 up to 4 IDE devices, 2 x SATA 1.5G, RAID,0,1,JBOD, SATA_HDD Hotplug.
RAM Sockets: 4 x DDR400 up to 4GB.
Additional characteristics: onboard Realtek ALC850 8channel AC'97 audio codec, Realtek RTL8201CL 10/100 Ethernet LAN PHY.
BIOS: 2Mb AMI BIOS with ACPI, SM BIOS 3.0, PnP.
  The first motherboard cost about 95 euros and the second ~80 euros. Both of them are good choices because they support dual channel RAM and they have onboard good enough GPUs for an HTPC. Also they support all today's amd 939 CPUs. On the other hand the third motherboard has an 8 channel audio codec and costs about 65 euros only!