Buffalo WZR-HP-G450H

Product page (US)

Per this DD-WRT forums post, the shields are soldered on preventing removal for chip identification. The wireless chip appears to be an AR9381 or AR9384.. as the AR9384 does not seem to exist, it can be assumed the device uses AR9381. This post on wifi.com.cn says the device uses AR7242, AR8316, AR9381, and has 32MB + 64 MB of Flash and RAM.. respectively. The AR8316 is visible in the FCC photos.

DD-WRT router info screenshot confirming AR7242, the default FW is DD-WRT

The FCC photos show the device with an MAC sticker with an OUI of 4C:E6:76.

On Newegg (reviews)

Specs
Platform Serial Num. = ? FCC ID = FDI-09101912-0 Industry Canada ID = 6102A-036 CPU Type = Atheros AR7242 MIPS Rev = ? CPU Speed = 400 MHz Bus = ? Flash Type = ? Flash Chip = Macronix Model? x 2 Flash Size Chip1 = 32 MB Flash Size Chip1 = 32 MB Max Firmware Size = ? RAM Size = 64 MB RAM Chip = ? nvram Size = ? ETH chip1 = Atheros AR7242 Switch = Atheros AR8316 Port-based vlan = ? 802.1q vlan = ? Ethernet Port Count = 1-10/100/1000-WAN 4-10/100/1000-LAN Wired Standard = IEEE 802.3/3u/3ab Ethernet interface OUI = none specified boot_wait = ? bootloader = ? Flash Card Socket/Type = No SD/MMC Mod Support = No Expansion IF types = No PoE = No Power = 12 VDC, 1.5 A Connector type/size = Barrel plug LEDs/Color = ? Size = 6.5 x 6.2 x 2.2 in. USB = 1x USB 2.0 Serial Port = ? JTAG Port = ? Supported by TJTAG/Version = ? Supported by dd-wrt as of = WIP 15762 dd-wrt K2.4 Support = ? dd-wrt K2.6 Support = ? Special Features = ? Radio Wireless Radio = Atheros AR9381 WLAN DSP processor = Atheros AR7242 Wireless interface OUI = none specified Antenna Connector Type = 3 external omni-directional (3x3) RP-SMA MIMO status = 3x3:3 Wireless Standard = IEEE 802.11b/g/n 802.11n = up to 450 Mbps 802.11g = 6, 9, 12, 18, 24, 36, 48, 54 Mbps 802.11b = 1, 2, 5.5, 11 Mbps WiFi Operating Frequency = 2.4 GHz Radio cor_rev = ? Radio Capabilities = ? Other Default IP address = ? Default login user = ? Default login password = ? Default SSID = ? OEM = ? 3rd Party Firmware Support = ?

Flashing
Outside the USA the proprietary Buffalo firmware is available, starting at the initial 1.75 followed by 1.76 and as begin 2012 the 1.85 version. But outside the USA it ships with a "professional firmware" installed and this is a DD-WRT firmware with Buffalo Logo. Both flavors can be obtained from http://www.buffalo-technology.com, the European Buffalo site.

Serial Pinouts
Top Row: gnd, rx, tx, vcc Bottom Row: rx, tx, gnd, vcc

Pictures
FCCID FDI-09101912-0