User Guide

Installing the Motherboard
User’s Manual
2-7
Step 5. Insert the DDR DIMM module into the expansion
socket as shown in the illustration. Note how the
module is keyed to the socket. You can refer to
Figure 2-6 for the details. This insures the DDR
DIMM module will be plugged into the socket in
one way only. Firmly press the DDR DIMM
module into DDR DIMM socket, making certain
the module is completely seated in the DDR
DIMM socket.
Step 6. Once the DDR DIMM module has been installed,
the installation is complete and the computer’s
cover can be replaced. Or you can continue to
install other devices and add-on cards that are
mentioned in the following section.
Note
When you install a DDR DIMM module fully into the DDR DIMM socket, the eject tab should be
locked into the DDR DIMM module very firmly and fit into its indention on the both sides.
It is difficult to differentiate between the PC1600 and PC2100 DDR SDRAM modules from the exterior.
The only way you can identify them is to look at the sticker on the DDR SDRAM module. The sticker
will tell you which kind of structure module the DDR SDRAM is.
Frequency Asked Question About DDR DIMM Memory
Does the KR7A/KR7A-RAID motherboard support ECC memory?
Yes, the KR7A/KR7A-RAID does support ECC memory modules.
It supports up to 3 GB of non-registered memory, or 4 GB of registered memory. The maximum DDR
memory support of KR7A/KR7A-RAID is 3.5 GB rather than 4 GB. This limitation is caused by the PC
architecture. The missing 0.5 G memory address is reserved for PCI I/O space, AGP aperture mapping
space and other onboard device I/O space, so although the KT266A datasheet states that the memory
support is up to 4 GB, the system only uses about 3.5 GB with four 1 GB DDR memory installed. In
another words, BIOS and operating system will only report 3.5 GB.
Why does the power on process take longer time for KR7A/KR7A-RAID system? Is there any
memory compatibility issue? (KR7A/KR7A-RAID and other KT266A chipset board)
While KR7A/KR7A-RAID system is powered on, the BIOS will do a memory checking process and it
takes about 5 ~ 15 seconds, then continue POST sequence.
According to the datasheet of VIA KT266A chipset (Revision 2.1, September 14, 2001), x 4 bit memory
chip is not supported.
Page 3, Advanced High-Performance SDR/DDR DRAM Controller
Supports 8 banks up to 4 GB DRAMs (512Mb x 8/x 16 DRAM technology) for registered SDR/DDR
modules
Supports 6 banks up to 3 GB DRAMs (512Mb x 8/x 16 DRAM technology) for unbuffered SDR/DDR