Haven't played around with it too much, but things generally seem to work. Obviously the Atheros AR5424 doesn't work (b/c it isn't supported) and I haven't tried sound yet. If anyone wants/needs me to try something specific, let me know and I'll try to help.
MP Kernel (AFAIK, cpu1 is just hyperthreading): OpenBSD 4.5-current (GENERIC.MP) #56: Tue Jun 9 14:51:31 MDT 2009 dera...@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC.MP cpu0: Intel(R) Atom(TM) CPU N270 @ 1.60GHz ("GenuineIntel" 686-class) 1.60 GHz cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,SSE3,MWAIT,DS-CPL,EST,TM2,xTPR real mem = 1063677952 (1014MB) avail mem = 1020129280 (972MB) mainbus0 at root bios0 at mainbus0: AT/286+ BIOS, date 04/13/09, BIOS32 rev. 0 @ 0xfd5f0, SMBIOS rev. 2.5 @ 0xdf010 (36 entries) bios0: vendor Phoenix Technologies Ltd. version "04D0.M002.20090413.KTW" date 04/13/2009 bios0: SAMSUNG ELECTRONICS CO., LTD. NC10/N110 acpi0 at bios0: rev 2 acpi0: tables DSDT FACP APIC HPET MCFG TCPA TMOR APIC BOOT SLIC SSDT SSDT SSDT acpi0: wakeup devices HDEF(S4) PXS1(S4) PXS2(S4) PXS3(S4) USB1(S3) USB2(S3) USB3(S3) USB4(S3) USB7(S3) SLT0(S4) SLT1(S4) SLT2(S4) SLT3(S4) SLT6(S4) LANC(S4) PWRB(S4) acpitimer0 at acpi0: 3579545 Hz, 24 bits acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: apic clock running at 132MHz cpu1 at mainbus0: apid 1 (application processor) cpu1: Intel(R) Atom(TM) CPU N270 @ 1.60GHz ("GenuineIntel" 686-class) 1.60 GHz cpu1: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,SSE3,MWAIT,DS-CPL,EST,TM2,xTPR ioapic0 at mainbus0: apid 1 pa 0xfec00000, version 20, 24 pins ioapic0: misconfigured as apic 2, remapped to apid 1 acpihpet0 at acpi0: 14318179 Hz acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus 2 (RP01) acpiprt2 at acpi0: bus -1 (RP02) acpiprt3 at acpi0: bus 3 (RP03) acpiprt4 at acpi0: bus 4 (PCIB) acpiec0 at acpi0 acpicpu0 at acpi0: C3, C2 acpicpu1 at acpi0: C3, C2 acpipwrres0 at acpi0: FN00 acpitz0 at acpi0: critical temperature 98 degC acpibat0 at acpi0: BAT1 type LION oem "SAMSUNG Electronics" acpiac0 at acpi0: AC unit online acpibtn0 at acpi0: LID0 acpibtn1 at acpi0: PWRB acpibtn2 at acpi0: SLPB acpivideo0 at acpi0: GFX0 acpivout0 at acpivideo0: DD01 acpivout1 at acpivideo0: DD02 acpivout2 at acpivideo0: DD03 acpivout3 at acpivideo0: DD04 acpivout4 at acpivideo0: DD05 bios0: ROM list: 0xc0000/0xec00! 0xdf000/0x1000! 0xe0000/0x1800! cpu0: unknown Enhanced SpeedStep CPU, msr 0x060f0c2006000c20 cpu0: using only highest and lowest power states cpu0: Enhanced SpeedStep 1596 MHz: speeds: 1600, 800 MHz pci0 at mainbus0 bus 0: configuration mode 1 (bios) pchb0 at pci0 dev 0 function 0 "Intel 82945GME Host" rev 0x03 vga1 at pci0 dev 2 function 0 "Intel 82945GME Video" rev 0x03 wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation) wsdisplay0: screen 1-5 added (80x25, vt100 emulation) intagp0 at vga1 agp0 at intagp0: aperture at 0xd0000000, size 0x10000000 inteldrm0 at vga1: apic 1 int 16 (irq 11) drm0 at inteldrm0 "Intel 82945GM Video" rev 0x03 at pci0 dev 2 function 1 not configured azalia0 at pci0 dev 27 function 0 "Intel 82801GB HD Audio" rev 0x02: apic 1 int 22 (irq 5) azalia0: codecs: Realtek ALC272 audio0 at azalia0 ppb0 at pci0 dev 28 function 0 "Intel 82801GB PCIE" rev 0x02: apic 1 int 17 (irq 10) pci1 at ppb0 bus 2 ath0 at pci1 dev 0 function 0 "Atheros AR5424" rev 0x01: apic 1 int 16 (irq 11) ath0: AR5424 14.2 phy 7.0 rf 0.0, WOR4W, address 00:24:d2:6a:b5:0b ppb1 at pci0 dev 28 function 2 "Intel 82801GB PCIE" rev 0x02: apic 1 int 18 (irq 5) pci2 at ppb1 bus 3 mskc0 at pci2 dev 0 function 0 "Marvell Yukon 88E8040" rev 0x13, Yukon-2 FE+ rev. A0 (0x0): apic 1 int 18 (irq 5) msk0 at mskc0 port A: address 00:13:77:f7:a2:c0 eephy0 at msk0 phy 0: 88E3016 10/100 PHY, rev. 0 uhci0 at pci0 dev 29 function 0 "Intel 82801GB USB" rev 0x02: apic 1 int 23 (irq 5) uhci1 at pci0 dev 29 function 1 "Intel 82801GB USB" rev 0x02: apic 1 int 19 (irq 5) uhci2 at pci0 dev 29 function 2 "Intel 82801GB USB" rev 0x02: apic 1 int 18 (irq 5) uhci3 at pci0 dev 29 function 3 "Intel 82801GB USB" rev 0x02: apic 1 int 16 (irq 11) ehci0 at pci0 dev 29 function 7 "Intel 82801GB USB" rev 0x02: apic 1 int 23 (irq 5) usb0 at ehci0: USB revision 2.0 uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1 ppb2 at pci0 dev 30 function 0 "Intel 82801BAM Hub-to-PCI" rev 0xe2 pci3 at ppb2 bus 4 ichpcib0 at pci0 dev 31 function 0 "Intel 82801GBM LPC" rev 0x02: PM disabled pciide0 at pci0 dev 31 function 2 "Intel 82801GBM SATA" rev 0x02: DMA, channel 0 wired to compatibility, channel 1 wired to compatibility wd0 at pciide0 channel 0 drive 0: <SAMSUNG HM160HI> wd0: 16-sector PIO, LBA48, 152627MB, 312581808 sectors wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5 ichiic0 at pci0 dev 31 function 3 "Intel 82801GB SMBus" rev 0x02: apic 1 int 19 (irq 5) iic0 at ichiic0 spdmem0 at iic0 addr 0x50: 1GB DDR2 SDRAM non-parity PC2-6400CL5 SO-DIMM usb1 at uhci0: USB revision 1.0 uhub1 at usb1 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb2 at uhci1: USB revision 1.0 uhub2 at usb2 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb3 at uhci2: USB revision 1.0 uhub3 at usb3 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb4 at uhci3: USB revision 1.0 uhub4 at usb4 "Intel UHCI root hub" rev 1.00/1.00 addr 1 isa0 at ichpcib0 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 pms0 at pckbc0 (aux slot) pckbc0: using irq 12 for aux slot wsmouse0 at pms0 mux 0 pcppi0 at isa0 port 0x61 midi0 at pcppi0: <PC speaker> spkr0 at pcppi0 npx0 at isa0 port 0xf0/16: reported by CPUID; using exception 16 mtrr: Pentium Pro MTRR support run0 at uhub0 port 5 "Cisco-Linksys LLC Dual-Band Wireless-N USB Network Adapter" rev 2.00/1.01 addr 2 run0: MAC/BBP RT2872 (rev 0x0202), RF RT2850 (MIMO 2T2R), address 00:1e:e5:e7:47:28 umass0 at uhub0 port 6 configuration 1 interface 0 " USB Flash Memory" rev 2.00/1.00 addr 3 umass0: using SCSI over Bulk-Only scsibus0 at umass0: 2 targets, initiator 0 sd0 at scsibus0 targ 1 lun 0: <, USB Flash Memory, PMAP> SCSI0 0/direct removable sd0: 3875MB, 512 bytes/sec, 7936000 sec total uvideo0 at uhub0 port 8 configuration 1 interface 0 "Vimicro Corp. Namuga 1.3M Webcam" rev 2.00/1.00 addr 4 video0 at uvideo0 ubt0 at uhub2 port 2 "Broadcom Corp BCM92045NMD" rev 2.00/3.54 addr 2 softraid0 at root root on sd0a swap on sd0b dump on sd0b Now SP kernel: OpenBSD 4.5-current (GENERIC) #48: Tue Jun 9 14:43:41 MDT 2009 dera...@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC cpu0: Intel(R) Atom(TM) CPU N270 @ 1.60GHz ("GenuineIntel" 686-class) 1.60 GHz cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,SSE3,MWAIT,DS-CPL,EST,TM2,xTPR real mem = 1063677952 (1014MB) avail mem = 1020153856 (972MB) mainbus0 at root bios0 at mainbus0: AT/286+ BIOS, date 04/13/09, BIOS32 rev. 0 @ 0xfd5f0, SMBIOS rev. 2.5 @ 0xdf010 (36 entries) bios0: vendor Phoenix Technologies Ltd. version "04D0.M002.20090413.KTW" date 04/13/2009 bios0: SAMSUNG ELECTRONICS CO., LTD. NC10/N110 acpi0 at bios0: rev 2 acpi0: tables DSDT FACP APIC HPET MCFG TCPA TMOR APIC BOOT SLIC SSDT SSDT SSDT acpi0: wakeup devices HDEF(S4) PXS1(S4) PXS2(S4) PXS3(S4) USB1(S3) USB2(S3) USB3(S3) USB4(S3) USB7(S3) SLT0(S4) SLT1(S4) SLT2(S4) SLT3(S4) SLT6(S4) LANC(S4) PWRB(S4) acpitimer0 at acpi0: 3579545 Hz, 24 bits acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: apic clock running at 132MHz cpu at mainbus0: not configured ioapic0 at mainbus0: apid 1 pa 0xfec00000, version 20, 24 pins ioapic0: misconfigured as apic 2, remapped to apid 1 acpihpet0 at acpi0: 14318179 Hz acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus 2 (RP01) acpiprt2 at acpi0: bus -1 (RP02) acpiprt3 at acpi0: bus 3 (RP03) acpiprt4 at acpi0: bus 4 (PCIB) acpiec0 at acpi0 acpicpu0 at acpi0: C3, C2 acpipwrres0 at acpi0: FN00 acpitz0 at acpi0: critical temperature 98 degC acpibat0 at acpi0: BAT1 type LION oem "SAMSUNG Electronics" acpiac0 at acpi0: AC unit online acpibtn0 at acpi0: LID0 acpibtn1 at acpi0: PWRB acpibtn2 at acpi0: SLPB acpivideo0 at acpi0: GFX0 acpivout0 at acpivideo0: DD01 acpivout1 at acpivideo0: DD02 acpivout2 at acpivideo0: DD03 acpivout3 at acpivideo0: DD04 acpivout4 at acpivideo0: DD05 bios0: ROM list: 0xc0000/0xec00! 0xdf000/0x1000! 0xe0000/0x1800! cpu0: unknown Enhanced SpeedStep CPU, msr 0x060f0c2006000c20 cpu0: using only highest and lowest power states cpu0: Enhanced SpeedStep 1597 MHz: speeds: 1600, 800 MHz pci0 at mainbus0 bus 0: configuration mode 1 (bios) pchb0 at pci0 dev 0 function 0 "Intel 82945GME Host" rev 0x03 vga1 at pci0 dev 2 function 0 "Intel 82945GME Video" rev 0x03 wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation) wsdisplay0: screen 1-5 added (80x25, vt100 emulation) intagp0 at vga1 agp0 at intagp0: aperture at 0xd0000000, size 0x10000000 inteldrm0 at vga1: apic 1 int 16 (irq 11) drm0 at inteldrm0 "Intel 82945GM Video" rev 0x03 at pci0 dev 2 function 1 not configured azalia0 at pci0 dev 27 function 0 "Intel 82801GB HD Audio" rev 0x02: apic 1 int 22 (irq 5) azalia0: codecs: Realtek ALC272 audio0 at azalia0 ppb0 at pci0 dev 28 function 0 "Intel 82801GB PCIE" rev 0x02: apic 1 int 17 (irq 10) pci1 at ppb0 bus 2 ath0 at pci1 dev 0 function 0 "Atheros AR5424" rev 0x01: apic 1 int 16 (irq 11) ath0: AR5424 14.2 phy 7.0 rf 0.0, WOR4W, address 00:24:d2:6a:b5:0b ppb1 at pci0 dev 28 function 2 "Intel 82801GB PCIE" rev 0x02: apic 1 int 18 (irq 5) pci2 at ppb1 bus 3 mskc0 at pci2 dev 0 function 0 "Marvell Yukon 88E8040" rev 0x13, Yukon-2 FE+ rev. A0 (0x0): apic 1 int 18 (irq 5) msk0 at mskc0 port A: address 00:13:77:f7:a2:c0 eephy0 at msk0 phy 0: 88E3016 10/100 PHY, rev. 0 uhci0 at pci0 dev 29 function 0 "Intel 82801GB USB" rev 0x02: apic 1 int 23 (irq 5) uhci1 at pci0 dev 29 function 1 "Intel 82801GB USB" rev 0x02: apic 1 int 19 (irq 5) uhci2 at pci0 dev 29 function 2 "Intel 82801GB USB" rev 0x02: apic 1 int 18 (irq 5) uhci3 at pci0 dev 29 function 3 "Intel 82801GB USB" rev 0x02: apic 1 int 16 (irq 11) ehci0 at pci0 dev 29 function 7 "Intel 82801GB USB" rev 0x02: apic 1 int 23 (irq 5) usb0 at ehci0: USB revision 2.0 uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1 ppb2 at pci0 dev 30 function 0 "Intel 82801BAM Hub-to-PCI" rev 0xe2 pci3 at ppb2 bus 4 ichpcib0 at pci0 dev 31 function 0 "Intel 82801GBM LPC" rev 0x02: PM disabled pciide0 at pci0 dev 31 function 2 "Intel 82801GBM SATA" rev 0x02: DMA, channel 0 wired to compatibility, channel 1 wired to compatibility wd0 at pciide0 channel 0 drive 0: <SAMSUNG HM160HI> wd0: 16-sector PIO, LBA48, 152627MB, 312581808 sectors wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5 ichiic0 at pci0 dev 31 function 3 "Intel 82801GB SMBus" rev 0x02: apic 1 int 19 (irq 5) iic0 at ichiic0 spdmem0 at iic0 addr 0x50: 1GB DDR2 SDRAM non-parity PC2-6400CL5 SO-DIMM usb1 at uhci0: USB revision 1.0 uhub1 at usb1 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb2 at uhci1: USB revision 1.0 uhub2 at usb2 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb3 at uhci2: USB revision 1.0 uhub3 at usb3 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb4 at uhci3: USB revision 1.0 uhub4 at usb4 "Intel UHCI root hub" rev 1.00/1.00 addr 1 isa0 at ichpcib0 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 pms0 at pckbc0 (aux slot) pckbc0: using irq 12 for aux slot wsmouse0 at pms0 mux 0 pcppi0 at isa0 port 0x61 midi0 at pcppi0: <PC speaker> spkr0 at pcppi0 npx0 at isa0 port 0xf0/16: reported by CPUID; using exception 16 mtrr: Pentium Pro MTRR support run0 at uhub0 port 5 "Cisco-Linksys LLC Dual-Band Wireless-N USB Network Adapter" rev 2.00/1.01 addr 2 run0: MAC/BBP RT2872 (rev 0x0202), RF RT2850 (MIMO 2T2R), address 00:1e:e5:e7:47:28 umass0 at uhub0 port 6 configuration 1 interface 0 " USB Flash Memory" rev 2.00/1.00 addr 3 umass0: using SCSI over Bulk-Only scsibus0 at umass0: 2 targets, initiator 0 sd0 at scsibus0 targ 1 lun 0: <, USB Flash Memory, PMAP> SCSI0 0/direct removable sd0: 3875MB, 512 bytes/sec, 7936000 sec total uvideo0 at uhub0 port 8 configuration 1 interface 0 "Vimicro Corp. Namuga 1.3M Webcam" rev 2.00/1.00 addr 4 video0 at uvideo0 ubt0 at uhub2 port 2 "Broadcom Corp BCM92045NMD" rev 2.00/3.54 addr 2 softraid0 at root root on sd0a swap on sd0b dump on sd0b