Seems to work with very light testing and bsd-kernel.
bsd.mp won't boot on this box (wd0 timeouts).

bge0 at pci0 dev 11 function 0 "Broadcom BCM5788" rev 0x03, BCM5705 A3
(0x3003): irq 10, address 00:0c:76:3e:6d:c4
brgphy0 at bge0 phy 1: BCM5705 10/100/1000baseT PHY, rev. 2

and whole:

OpenBSD 4.2-current (GENERIC.MP) #285: Sat Oct 13 14:12:29 MDT 2007
deraadt@i386.openbsd.org:/usr/src/sy...ile/GENERIC.MP
cpu0: AMD Athlon(tm) XP 2200+ ("AuthenticAMD" 686-class, 256KB L2 cache) 1.81 GHz
cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,P GE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE
real mem = 804810752 (767MB)
avail mem = 769843200 (734MB)
mainbus0 at root
bios0 at mainbus0: AT/286+ BIOS, date 09/05/03, BIOS32 rev. 0 @ 0xfdaf0, SMBIOS rev. 2.3 @ 0xf0630 (22 entries)
bios0: vendor American Megatrends Inc. version "Version 07.00T" date 04/02/01
bios0: MSI MS-6590
apm0 at bios0: Power Management spec V1.2
apm0: AC on, battery charge unknown
apm0: flags 30102 dobusy 0 doidle 1
pcibios0 at bios0: rev 2.1 @ 0xf0000/0x10000
pcibios0: PCI IRQ Routing Table rev 1.0 @ 0xf7fb0/240 (13 entries)
pcibios0: PCI Interrupt Router at 000:17:0 ("VIA VT8237 ISA" rev 0x00)
pcibios0: PCI bus #1 is the last bus
bios0: ROM list: 0xc0000/0xf800 0xcf800/0x4400! 0xd4000/0x1800
mainbus0: Intel MP Specification (Version 1.4)
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: apic clock running at 267 MHz
mainbus0: bus 0 is type PCI
mainbus0: bus 1 is type PCI
mainbus0: bus 2 is type ISA
ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 3, 24 pins
pci0 at mainbus0 bus 0: configuration mode 1 (no bios)
pchb0 at pci0 dev 0 function 0 "VIA VT8377 PCI" rev 0x80
ppb0 at pci0 dev 1 function 0 "VIA VT8377 AGP" rev 0x00
pci_intr_map: bus 0 dev 1 func 0 pin 1; line 11
pci_intr_map: no MP mapping found
pci_intr_map: bus 0 dev 1 func 0 pin 2; line 5
pci_intr_map: no MP mapping found
pci1 at ppb0 bus 1
vga1 at pci1 dev 0 function 0 "NVIDIA GeForce FX 5500" rev 0xa1
wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation)
wsdisplay0: screen 1-5 added (80x25, vt100 emulation)
emu0 at pci0 dev 10 function 0 "Creative Labs SoundBlaster Audigy" rev 0x03: apic 2 int 17 (irq 5)
ac97: codec id 0x54524123 (TriTech Microelectronics TR28602)
audio0 at emu0
"Creative Labs SoundBlaster Audigy Digital" rev 0x03 at pci0 dev 10 function 1 not configured
"Creative Labs Firewire" rev 0x00 at pci0 dev 10 function 2 not configured
bge0 at pci0 dev 11 function 0 "Broadcom BCM5788" rev 0x03, BCM5705 A3 (0x3003): apic 2 int 18 (irq 10), address 00:0c:76:3e:6d:c4
brgphy0 at bge0 phy 1: BCM5705 10/100/1000baseT PHY, rev. 2
"VIA VT6306 FireWire" rev 0x46 at pci0 dev 14 function 0 not configured
pciide0 at pci0 dev 15 function 0 "VIA VT6420 SATA" rev 0x80: DMA
pci_intr_map: bus 0 dev 15 func 0 pin 2; line 11
pci_intr_map: no MP mapping found
pciide0: using irq 11 for native-PCI interrupt
wd0 at pciide0 channel 0 drive 0: <ST3250824AS>
wd0: 16-sector PIO, LBA48, 238475MB, 488397168 sectors
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5
pciide1 at pci0 dev 15 function 1 "VIA VT82C571 IDE" rev 0x06: ATA133, channel 0 configured to compatibility, channel 1 configured to compatibility
pciide1: channel 0 disabled (no drives)
atapiscsi0 at pciide1 channel 1 drive 0
scsibus0 at atapiscsi0: 2 targets
cd0 at scsibus0 targ 0 lun 0: <PLEXTOR, DVDR PX-708A, 1.08> SCSI0 5/cdrom removable
cd0(pciide1:1:0): using PIO mode 4, Ultra-DMA mode 2
uhci0 at pci0 dev 16 function 0 "VIA VT83C572 USB" rev 0x81: apic 2 int 21 (irq 11)
uhci1 at pci0 dev 16 function 1 "VIA VT83C572 USB" rev 0x81: apic 2 int 21 (irq 11)
uhci2 at pci0 dev 16 function 2 "VIA VT83C572 USB" rev 0x81: apic 2 int 21 (irq 5)
uhci3 at pci0 dev 16 function 3 "VIA VT83C572 USB" rev 0x81: apic 2 int 21 (irq 5)
ehci0 at pci0 dev 16 function 4 "VIA VT6202 USB" rev 0x86: apic 2 int 21 (irq 10)
ehci0: timed out waiting for BIOS
usb0 at ehci0: USB revision 2.0
uhub0 at usb0 "VIA EHCI root hub" rev 2.00/1.00 addr 1
viapm0 at pci0 dev 17 function 0 "VIA VT8237 ISA" rev 0x00
iic0 at viapm0
iic0: addr 0x2f 04=00 06=0b 07=00 0c=00 0d=07 0e=84 0f=00 10=c0 11=10 12=00 13=60 14=14 15=62 16=01 17=06
spdmem0 at iic0 addr 0x50: 256MB DDR SDRAM non-parity PC-3200CL3.0
spdmem1 at iic0 addr 0x51: 256MB DDR SDRAM non-parity PC-2100CL2.5
spdmem2 at iic0 addr 0x52: 256MB DDR SDRAM non-parity PC-3200CL3.0
usb1 at uhci0: USB revision 1.0
uhub1 at usb1 "VIA UHCI root hub" rev 1.00/1.00 addr 1
usb2 at uhci1: USB revision 1.0
uhub2 at usb2 "VIA UHCI root hub" rev 1.00/1.00 addr 1
usb3 at uhci2: USB revision 1.0
uhub3 at usb3 "VIA UHCI root hub" rev 1.00/1.00 addr 1
usb4 at uhci3: USB revision 1.0
uhub4 at usb4 "VIA UHCI root hub" rev 1.00/1.00 addr 1
isa0 at mainbus0
isadma0 at isa0
pckbc0 at isa0 port 0x60/5
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pmsi0 at pckbc0 (aux slot)
pckbc0: using irq 12 for aux slot
wsmouse0 at pmsi0 mux 0
pcppi0 at isa0 port 0x61
midi0 at pcppi0: <PC speaker>
spkr0 at pcppi0
lpt0 at isa0 port 0x378/4 irq 7
lm0 at isa0 port 0x290/8: W83697HF
npx0 at isa0 port 0xf0/16: reported by CPUID; using exception 16
pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo
pccom1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo
fdc0 at isa0 port 0x3f0/6 irq 6 drq 2
pctr: user-level performance counters enabled
mtrr: Pentium Pro MTRR support
uscanner0 at uhub2 port 2 "Canon CanoScan" rev 1.00/1.00 addr 2
uhidev0 at uhub3 port 2 configuration 1 interface 0 "BTC USB Multimedia Keyboard" rev 1.10/1.30 addr 2
uhidev0: iclass 3/1
ukbd0 at uhidev0: 8 modifier keys, 6 key codes
wskbd1 at ukbd0 mux 1
wskbd1: connecting to wsdisplay0
uhidev1 at uhub3 port 2 configuration 1 interface 1 "BTC USB Multimedia Keyboard" rev 1.10/1.
OpenBSD 4.2-current (GENERIC) #429: Sat Oct 13 13:57:25 MDT 2007
deraadt@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC
cpu0: AMD Athlon(tm) XP 2200+ ("AuthenticAMD" 686-class, 256KB L2 cache) 1.81 GHz
cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,P GE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE
real mem = 804810752 (767MB)
avail mem = 769900544 (734MB)
mainbus0 at root
bios0 at mainbus0: AT/286+ BIOS, date 09/05/03, BIOS32 rev. 0 @ 0xfdaf0, SMBIOS rev. 2.3 @ 0xf0630 (22 entries)
bios0: vendor American Megatrends Inc. version "Version 07.00T" date 04/02/01
bios0: MSI MS-6590
apm0 at bios0: Power Management spec V1.2
apm0: AC on, battery charge unknown
apm0: flags 30102 dobusy 0 doidle 1
pcibios0 at bios0: rev 2.1 @ 0xf0000/0x10000
pcibios0: PCI IRQ Routing Table rev 1.0 @ 0xf7fb0/240 (13 entries)
pcibios0: PCI Interrupt Router at 000:17:0 ("VIA VT8237 ISA" rev 0x00)
pcibios0: PCI bus #1 is the last bus
bios0: ROM list: 0xc0000/0xf800 0xcf800/0x4400! 0xd4000/0x1800
cpu0 at mainbus0
pci0 at mainbus0 bus 0: configuration mode 1 (no bios)
pchb0 at pci0 dev 0 function 0 "VIA VT8377 PCI" rev 0x80
ppb0 at pci0 dev 1 function 0 "VIA VT8377 AGP" rev 0x00
pci1 at ppb0 bus 1
vga1 at pci1 dev 0 function 0 "NVIDIA GeForce FX 5500" rev 0xa1
wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation)
wsdisplay0: screen 1-5 added (80x25, vt100 emulation)
emu0 at pci0 dev 10 function 0 "Creative Labs SoundBlaster Audigy" rev 0x03: irq 5
ac97: codec id 0x54524123 (TriTech Microelectronics TR28602)
audio0 at emu0
"Creative Labs SoundBlaster Audigy Digital" rev 0x03 at pci0 dev 10 function 1 not configured
"Creative Labs Firewire" rev 0x00 at pci0 dev 10 function 2 not configured
bge0 at pci0 dev 11 function 0 "Broadcom BCM5788" rev 0x03, BCM5705 A3 (0x3003): irq 10, address 00:0c:76:3e:6d:c4
brgphy0 at bge0 phy 1: BCM5705 10/100/1000baseT PHY, rev. 2
"VIA VT6306 FireWire" rev 0x46 at pci0 dev 14 function 0 not configured
pciide0 at pci0 dev 15 function 0 "VIA VT6420 SATA" rev 0x80: DMA
pciide0: using irq 11 for native-PCI interrupt
wd0 at pciide0 channel 0 drive 0: <ST3250824AS>
wd0: 16-sector PIO, LBA48, 238475MB, 488397168 sectors
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5
pciide1 at pci0 dev 15 function 1 "VIA VT82C571 IDE" rev 0x06: ATA133, channel 0 configured to compatibility, channel 1 configured to compatibility
pciide1: channel 0 disabled (no drives)
atapiscsi0 at pciide1 channel 1 drive 0
scsibus0 at atapiscsi0: 2 targets
cd0 at scsibus0 targ 0 lun 0: <PLEXTOR, DVDR PX-708A, 1.08> SCSI0 5/cdrom removable
cd0(pciide1:1:0): using PIO mode 4, Ultra-DMA mode 2
uhci0 at pci0 dev 16 function 0 "VIA VT83C572 USB" rev 0x81: irq 11
uhci1 at pci0 dev 16 function 1 "VIA VT83C572 USB" rev 0x81: irq 11
uhci2 at pci0 dev 16 function 2 "VIA VT83C572 USB" rev 0x81: irq 5
uhci3 at pci0 dev 16 function 3 "VIA VT83C572 USB" rev 0x81: irq 5
ehci0 at pci0 dev 16 function 4 "VIA VT6202 USB" rev 0x86: irq 10
ehci0: timed out waiting for BIOS
usb0 at ehci0: USB revision 2.0
uhub0 at usb0 "VIA EHCI root hub" rev 2.00/1.00 addr 1
viapm0 at pci0 dev 17 function 0 "VIA VT8237 ISA" rev 0x00
iic0 at viapm0
iic0: addr 0x2f 04=00 06=0b 07=00 0c=00 0d=07 0e=84 0f=00 10=c0 11=10 12=00 13=60 14=14 15=62 16=01 17=06
spdmem0 at iic0 addr 0x50: 256MB DDR SDRAM non-parity PC-3200CL3.0
spdmem1 at iic0 addr 0x51: 256MB DDR SDRAM non-parity PC-2100CL2.5
spdmem2 at iic0 addr 0x52: 256MB DDR SDRAM non-parity PC-3200CL3.0
usb1 at uhci0: USB revision 1.0
uhub1 at usb1 "VIA UHCI root hub" rev 1.00/1.00 addr 1
usb2 at uhci1: USB revision 1.0
uhub2 at usb2 "VIA UHCI root hub" rev 1.00/1.00 addr 1
usb3 at uhci2: USB revision 1.0
uhub3 at usb3 "VIA UHCI root hub" rev 1.00/1.00 addr 1
usb4 at uhci3: USB revision 1.0
uhub4 at usb4 "VIA UHCI root hub" rev 1.00/1.00 addr 1
isa0 at mainbus0
isadma0 at isa0
pckbc0 at isa0 port 0x60/5
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pmsi0 at pckbc0 (aux slot)
pckbc0: using irq 12 for aux slot
wsmouse0 at pmsi0 mux 0
pcppi0 at isa0 port 0x61
midi0 at pcppi0: <PC speaker>
spkr0 at pcppi0
lpt0 at isa0 port 0x378/4 irq 7
lm0 at isa0 port 0x290/8: W83697HF
npx0 at isa0 port 0xf0/16: reported by CPUID; using exception 16
pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo
pccom1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo
fdc0 at isa0 port 0x3f0/6 irq 6 drq 2
biomask ef65 netmask ef65 ttymask ffe7
pctr: user-level performance counters enabled
mtrr: Pentium Pro MTRR support
uhidev0 at uhub3 port 2 configuration 1 interface 0 "BTC USB Multimedia Keyboard" rev 1.10/1.30 addr 2
uhidev0: iclass 3/1
ukbd0 at uhidev0: 8 modifier keys, 6 key codes
wskbd1 at ukbd0 mux 1
wskbd1: connecting to wsdisplay0
uhidev1 at uhub3 port 2 configuration 1 interface 1 "BTC USB Multimedia Keyboard" rev 1.10/1.30 addr 2
uhidev1: iclass 3/0
uhidev1: 3 report ids
uhid0 at uhidev1 reportid 1: input=1, output=0, feature=0
uhid1 at uhidev1 reportid 2: input=3, output=0, feature=0
uhid2 at uhidev1 reportid 3: input=3, output=0, feature=4
uscanner0 at uhub2 port 2 "Canon CanoScan" rev 1.00/1.00 addr 2
dkcsum: wd0 matches BIOS drive 0x80
root on wd0a swap on wd0b dump on wd0b