915GM Datasheet, PDF (22/48 Pages) Intel Corporation – 915GM/PM/GME/GMS and 910GML/GMLE Express Chipset

Errata
22.
PCI Express SKP/InitFCx Contention
Problem:
During GMCH PCI Express initialization, if a SKP is being transmitted immediately
before an InitFCx DLLP, then a partial InitFCx may be transmitted.
Implication: A slight delay (less than 100 ns) may occur during link initialization. Device may
report correctable error. InitFCx will automatically be repeated.
Workaround: None
Status:
For the steppings affected, see the Summary Tables of Changes
23.
SMVREF High Current Draw
Problem:
When SMOCDCOMP[1:0] are connected to ground (either directly or through a pull-
down resistor), SMVREF[1:0] may draw significantly more current than specified. If
the corresponding voltage supply is not capable of handling the resulting current, the
SMVREF[1:0] voltage will droop below specification.
Implication: If SMVREF[1:0] droops below specification, the system may hang. Failure observed
during S3 only.
Workaround: Leave SMOCDCOMP[1:0] as NC (No Connect) for both DDR and DDR2 designs. This
limits the maximum current draw on SMVREF[1:0] to 200 µA (i.e. 100uA/pin). In
addition, use a voltage supply that can supply at least 200 µA (total) for
SMVREF[1:0].
Status:
For the steppings affected, see the Summary Tables of Changes.
24.
Mobile Intel 915GM/GMS/GME and 910GML/GMLE Express Chipset
Graphics Clock Crossing Issue
Problem:
While attempting to launch or exit an application that uses the overlay engine (e.g.
media playback software running a video clip), the system may hang (blue screen) or
screen resolution may change to VGA mode. This event may occur when a signal pulse
is missed inside the chip due to synchronization of the graphics render and display
clocks while graphics overlay mode is being turned off.
Implication: Failure is difficult to reproduce because this event only occurs under a very rare but
valid timing condition where graphics render and display clocks are aligned while the
graphics overlay is being turned off. System will hang or screen resolution may
change to VGA mode when launching or exiting an application that uses the overlay
engine. Mobile Intel 915GM/GMS/GME and 910GML/GMLE platforms that use render
clock at 166 MHz are not affected by this sighting.
Workaround: It is possible for BIOS to contain a workaround. Contact your Intel Field
Representative for more details.
Status:
For the steppings affected, see the Summary Tables of Changes.
22
Specification Update