Asus P5QL - Manual (Page 34)

2-12 Chapter 2: Hardware information
• When using only one DDR2 DIMM, start installing it from DIMM_A1 or
DIMM_B1 for better overclocking capability.
• For dual-channel configuration (1), install two identical DIMMs in DIMM_A1
and DIMM_B1.
• For dual-channel configuration (2), you can:
- install four identical DIMMs in all four slots; or
- install one identical DIMM pair in DIMM_A1 and DIMM_B1 (yellow
slots) and another identical DIMM pair in DIMM_A2 and DIMM_B2
(black slots).
• Always install DIMMs with the same CAS latency. For optimum compatibility,
it is recommended that you obtain memory modules from the same vendor.
• When you install a total memory of 4GB or more, Windows ® 32-bit
operating system may only recognize less than 3GB. Hence, a total
installed memory of less than 3GB is recommended if you are using a
Windows 32-bit operating system.
• This motherboard does not support memory modules made up of 128Mb
chips.
64-bit
Windows ® XP Professional x64 Edition
Windows ® Vista x64 Edition
This motherboard supports up to 16GB on the operating systems listed below.
You may install a maximum of 4GB DIMM on each slot.
• The default memory operation frequency is dependent on its SPD. Under
the default state, some memory modules for overclocking may operate at a
lower frequency than the vendor-marked value. To operate at the
vendor-marked or at a higher frequency, see section 3.4 Ai Tweaker menu
for manual memory frequency adjustment.
• The memory modules may require a better cooling system to work stably
under full loading (4 DIMMs) or overclocking setting.
• Some old-version DDR2-800 DIMMs may not match Intel ® ’s
On-Die-Termination (ODT) requirement and will automatically downgrade
to run at DDR2-667. If this happens, contact your memory vendor to check
the ODT value.
• Due to chipset limitation, DDR2-800 with CL=4 will be downgraded to run
at DDR2-667 by default setting. If you want to operate with lower latency,
adjust the memory timing manually.