Comment 16 for bug 379124

Confirmed problem on my Dell Inspiron 1545. This is using Karmic Beta with updates to 10/16/09.
Under jaunty I was able to work around this issue partially with the following Xorg.conf option:

Option "MigrationHeuristic" "Greedy"

However, this is no longer used by the intel driver.

lspci -vvnn

00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07)
 Subsystem: Dell Device [1028:02aa]
 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 Interrupt: pin A routed to IRQ 30
 Region 0: Memory at f6c00000 (64-bit, non-prefetchable) [size=4M]
 Region 2: Memory at e0000000 (64-bit, prefetchable) [size=256M]
 Region 4: I/O ports at efe8 [size=8]
 Capabilities: <access denied>
 Kernel driver in use: i915
 Kernel modules: i915

00:02.1 Display controller [0380]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a43] (rev 07)
 Subsystem: Dell Device [1028:02aa]
 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 Region 0: Memory at f6b00000 (64-bit, non-prefetchable) [size=1M]
 Capabilities: <access denied>