Filter
Top Products
CHAPTER 3 - BIOS SETUP
SYS7180VE User’s Manual
35
Description Choice
CAS Latency Time
When synchronous DRAM is installed, the
number of clock cycles of CAS latency depends
on the DRAM timing. Do not reset this field
from the default value specified by the system
designer.
You can select CAS latency time in HCLK of
2/2 or 3/3. The system board designer should set
the values in this field, depends on the DRAM
installed specifications of the installed DRAM
or the installed CPU.
Active to Precharge delay
Select the precharge delay timer.
DRAM RAS# to CAS# delay
This field lets you insert a timing delay between
the CAS and RAS strobe signals, used when
DRAM is written to, read from, or refreshed.
Fast gives faster performance; and Slow gives
more stable performance. This field applies only
when synchronous DRAM is installed in the
system.
DRAM RAS# Precharge
The precharge time is the number of cycles it
takes for the RAS to accumulate its charge
b
efore DRAM refresh. If insufficient time is
allowed, refresh may be incomplete and the
DRAM may fail to retain data.
CHAPTER 3 - BIOS SETUP
36
SYS7180VE User’s Manual
Description Choice
Memory Frequency for
Select the memory frequency for
DDR200/DDR266 when install the memory with
specification of DDR200, or when install the
memory with specification of DDR266, or Auto
define by the BIOS.
System BIOS Cacheable
Selecting Enabled allows caching of the system
BIOS ROM at F0000h-FFFFFh, resulting in
b
etter system performance. However, if any
program writes to this memory area, a system
error may result.
Video BIOS Cacheable
Selecting Enabled allows caching of the video
BIOS ROM at C0000h to C7FFFh, resulting in
b
etter video performance. However, if any
program writes to this memory area, a system
error may result.
Memory Hole At 15M-16M
You can reserve this area of system memory for
ISA adapter ROM. When this area is reserved, it
cannot be cached. The user information of
peripherals that need to use this area of system
memory usually discusses their memory
requirements.