Hi! 
it's a card detection problem & old via drivers bug

# lspci -vvv
01:00.0 VGA compatible controller: VIA Technologies, Inc. P4M900 [Chrome 9 HC] (rev 01) (prog-if 00 [VGA controller])
	Subsystem: Hewlett-Packard Company Device 3030
	Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz+ UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 64 (500ns min)
	Interrupt: pin A routed to IRQ 16
	Region 0: Memory at c0000000 (32-bit, prefetchable) [size=256M]
	Region 1: Memory at fc000000 (32-bit, non-prefetchable) [size=16M]
	Expansion ROM at fbff0000 [disabled] [size=64K]
	Capabilities: [60] Power Management version 2
		Flags: PMEClk- DSI+ D1+ D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
		Status: D0 PME-Enable- DSel=0 DScale=0 PME-
	Capabilities: [70] AGP version 3.0
		Status: RQ=256 Iso- ArqSz=0 Cal=7 SBA+ ITACoh- GART64- HTrans- 64bit- FW- AGP3+ Rate=x4,x8
		Command: RQ=1 ArqSz=0 Cal=0 SBA+ AGP- GART64- 64bit- FW- Rate=<none>

# lspci -n
01:00.0 0300: 1106:3371 (rev 01)

to correct it we need to add line in include/drm/drm_pciids.h

 diff -rupN include/drm/drm_pciids.h.bak include/drm/drm_pciids.h 
--- include/drm/drm_pciids.h.bak	2010-06-21 03:36:41.000000000 +0400
+++ include/drm/drm_pciids.h	2010-06-21 03:37:28.000000000 +0400
@@ -458,6 +458,7 @@
 	{0x1106, 0x3343, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0}, \
 	{0x1106, 0x3230, PCI_ANY_ID, PCI_ANY_ID, 0, 0, VIA_DX9_0}, \
 	{0x1106, 0x3157, PCI_ANY_ID, PCI_ANY_ID, 0, 0, VIA_PRO_GROUP_A}, \
+	{0x1106, 0x3371, PCI_ANY_ID, PCI_ANY_ID, 0, 0, VIA_DX9_0}, \
 	{0, 0, 0}
 
 #define i810_PCI_IDS \

ps: link to openchrome wiki : http://wiki.openchrome.org/tikiwiki/tiki-index.php?page=P4M900