Platform Design Checklist
R
304
Intel
®
855PM Chipset Platform Design Guide
14.7.1.1. AGP
Connector
AGP Connector Resistor Recommendations
Pin Name
System
Pull up/Pull down
Series
Damping
Notes
9
SERR#, PERR#
Pull up to Vcc1_5
8.2 k
PERR# and SERR# are not supported in
the MCH. An external pull up to a 1.5 V
source is required for AGP controllers
that implement these signals.
INTA#, INTB#
Route to the ICH4-M PIRQ signals.
14.7.1.2.
AGP Decoupling Recommendations
Intel 855PM MCH Interface – High Frequency Decoupling Recommendations
1
Pin Name
Configuration
F
Qty
Notes
9
Vcc1_5
Pull down to GND
0.01 µF
6
Place a minimum of six 0.01 µF within 70
mils of the outer row of balls on the MCH.
Place one extra 0.01 µF cap for every 10
vias that transition the AGP signal from
one reference signal plane to another.
Intel CRB uses 7x 0.1 µF, 1x 22 µF, and
1x 100 µF.
14.7.1.3.
AGP VREF Reference Voltage Dividers
MCH AGP Interface – Reference Voltage Dividers
Pin Name
System
Pull up/Pull down
Notes
9
AGPREF
Voltage divider
1 k
top)
1 k
bottom)
Source generated VREFs are recommended. See
Section 7.3.8 for more details.
See Figure 156 for impelementation on Intel CRB.