Chipset Features Setup

This section allows you to configure the system based on the specific features of the installed chipset. This chipset manages bus speeds and access to system memory resources, such as DRAM and the external cache. It also coordinates communications between the conventional ISA bus and the PCI bus

DRAM Settings

The first chipset settings deal with CPU access to dynamic random access memory (DRAM).

DRAM Burst of 4 Refresh

DRAM must continually be refreshed or it will lose its data. Normally, DRAM is refreshed entirely as the result of a single request. Enabling this option allows DRAM to be refreshed in a sequence of four short bursts occurring at 1/4 cycles.


Disabled   DRAM refreshes occur as single requests.     

Enabled    DRAM refreshes occur as four bursts at 1/4   
           cycle each.                                  



DRAM RAS# Active


Asserted   DRAM RAS# will be asserted after every DRAM  
           cycle.                                       

Deassert   DRAM RAS# will be deasserted after every     
           DRAM cycle making each DRAM cycle a "Row     
           miss".                                       



DRAM Refresh Mode

The cache DRAM controller offers two refresh modes, Normal and Hidden. In both modes, CAS takes place before RAS but the Normal mode requires a CPU cycle for each. On the other hand, a cycle is eliminated by "hiding" the CAS refresh in Hidden mode. Not only is the Hidden mode faster and more efficient, but it also allows the CPU to maintain the status of the cache even if the system goes into a power management "suspend" mode.


Normal    DRAM refresh using normal CPU        
          cycles                               

Hidden    DRAM refresh without CPU cycle for   
          CAS                                  



DRAM R/W Burst Timing

This allows DRAM read and write bursts to have their timings coordinated.


X444/X444  Both read and write DRAM timings are      
           X-4-4-4                                   

X444/X333  Read timing = X-4-4-4, write timing =     
           X-3-3-3                                   

X333/X333  Both read and write DRAM timings are      
           X-3-3-3                                   



Write Buffers

Write buffers are hardware features which improve the overall system performance by allowing the processor (or bus master) to continue its current execution without writing data to its final destination. The data is temporairily stored in fast buffers. The cache-DRAM controller contains three types of write buffers:

1. CPU to DRAM

2. CPU to PCI Bus

3. PCI to DRAM

CPU to DRAM Write Buffer


Enabled   Data will be cached in a fast        
          buffer and CPU will not be           
          interrupted                          

Disabled  Data will be written directly to     
          DRAM and the CPU will be             
          interrupted to control the write     
          operation.                           



CPU to PCI Write Buffer

When enabled, up to four Dwords of data can be sent to the PCI bus without interrupting the CPU. When disabled, a write buffer is not used and the CPU write cycle will not be completed until the PCI bus signals that it is ready to receive the data.


Enabled   CPU writes are buffered, more data   
          is written and the system operates   
          faster.                              

Disabled  CPU writes are not buffered and the  
          CPU is interrupted.                  



PCI to DRAM Write Buffer

If enabled, a pair of buffers, with a capacity of four Dwords each, are used to store data written from the PCI bus to memory. When disabled, PCI writes to DRAM are limited to a single transfer.


Enabled   PCI to DRAM writes are buffered      

Disabled  PCI to DRAM writes are not buffered  



Disabled is the default.

PCI Memory Burst Write

When enabled, the PCI bus will interpret CPU write cycles as the PCI burst protocol. This means that back-to-back sequential CPU memory write cycles addressed to the PCI will be translated into the fast PCI burst memory write cycles. This will directly improve the video performance when consecutive writes are initiated to a linear graphics frame buffer.


Enabled   PCI burst protocol used for          
          successive PCI memory writes.        

Disabled  Conventional write cycles are used.  



Disabled is the default.

Add Extra Wait for CAS#

CAS means Column Address Strobe. When DRAM is read from, written to or refreshed, the memory is addressed in terms of its column and row position. Enabling an extra wait for the CAS means that reads, writes or refreshes will take slightly longer.


Enabled   An extra wait state is used for CAS  

Disabled  No additional wait state used for    
          CAS                                  



Disabled is the default.

Add Extra Wait for RAS#

RAS means Row Address Strobe. When DRAM is read from, written to or refreshed, the memory is addressed in terms of its column and row position. Enabling an extra wait for the RAS means that reads, writes or refreshes will take slightly longer.


Enabled   An extra wait state is used for RAS  

Disabled  No additional wait state used for    
          RAS                                  



Disabled is the default.

Cache Features

System BIOS Cacheable

When enabled, accesses to the system BIOS ROM addressed at F0000H-FFFFFH are cached, provided that the cache controller is enabled.


Enabled   BIOS access cached                   

Disabled  BIOS access not cached               



Video BIOS Cacheable

As with caching the System BIOS above, enabling the Video BIOS cache will cause access to video BIOS addressed at C0000H to C7FFFH to be cached, if the cache controller is also enabled,


Enabled   Video BIOS access cached             

Disabled  Video BIOS access not cached         



L2 Cache Zero Wait State

The wait state is typically a function of the speed of the external cache. For a slower cache, disabling the L2 Cach Zero Wait State will cause the chipset to assert one wait state when accessing the external cache controller. When enabled, the chipset will not wait.


Enabled   Zero wait state                      

Disabled  One wait state                       



CPU-TO-PCI Byte Merge

When enabled, this allows data sent from the CPU to the PCI bus to be held in a buffer. The chipset will then write the data in the buffer to the PCI bus when appropriate.


Enabled   CPU-TO-PCI writes are buffered       

Disabled  Writes NOT buffered                  



VGA 128k Range Attribute

When enabled, this allows the chipset to apply features like "CPU-TO-PCI Byte Merge", "CPU-TO-PCI Prefetch" to be applied to VGA memory range A0000H-BFFFFH.


Enabled   VGA receives CPU-TO-PCI functions    

Disabled  Retain standard VGA interface.       



Memory Hole Start Address

In order to improve performance, certain space in memory is reserved for ISA cards. This memory must be mapped into the memory space below 16 MB. The user defined start address is the beginning address of this space.

The selections are from 1 to 15 with each number in MB. This selection will have no meaning if the memory hole is "disabled" (see below).

Memory Hole Size

This allows the user to define the size of the memory hole reserved for ISA cards. The options are "disabled", 64KB, 126KB, 256KB, 1MB, 2MB, 4MB, 8MB.

Power Management Setup

The Power Management Setup allows you to configure you system to most effectively save energy while operating in a manner consistent with your own style of computer use.

Power Management

This category allows you to select the type (or degree) of power saving and is directly related to the following modes:

1. Doze Mode

2. Standby Mode

3. Suspend Mode

4. HDD Power Down

There are four selections for Power Management, three of which have fixed mode settings.


Disable (default)  No power management.  Disables all four     
                   modes                                       

Min. Power Saving  Minimum power management.  Doze Mode = 1    
                   hr. Standby Mode = 1 hr., Suspend Mode = 1  
                   hr., and HDD Power Down = 15 min.           

Max. Power Saving  Maximum power management -- ONLY AVAILABLE  
                   FOR SL CPU'S.  Doze Mode = 1 min., Standby  
                   Mode = 1 min., Suspend Mode = 1 min., and   
                   HDD Power Down = 1 min.                     

User Defined       Allows you to set each mode individually.   
                   When not disabled, each of the ranges are   
                   from 1 min. to 1 hr. except for HDD Power   
                   Down which ranges from 1 min. to 15 min.    
                   and disable.                                



PM Control APM

When enabled, an Advanced Power Management device will be activated to enhance the Max. Power Saving mode and stop the CPU internal clock.

If the Max. Power Saving is not enabled, this will be preset to No.

Video Off Method

This determines the manner in which the monitor is blanked.


V/H SYNC+Blank     This selection will cause the system to     
                   turn off the vertical and horizontal        
                   synchronization ports and write blanks to   
                   the video buffer.                           

Blank Screen       This option only writes blanks to the       
                   video buffer.                               



PM Timers

The following four modes are Green PC power saving functions which are only user configurable when User Defined Power Management has been selected. See above for available selections.

Doze Mode

When enabled and after the set time of system inactivity, the CPU clock will run at at slower speed while all other devices still operate at full speed.

Standby Mode

When enabled and after the set time of system inactivity, the fixed disk drive and the video would be shut off while all other devices still operate at full speed.

Suspend Mode

When enabled and after the set time of system inactivity, all devices except the CPU will be shut off.

HDD Power Down

When enabled and after the set time of system inactivity, the hard disk drive will be powered down while all other devices remain active.

Power Down Activities

Power Down Activities events are I/O events whose occurrence can prevent the system from entering a power saving mode or can awaken the system from such a mode. In effect, the system remains alert for anything which occurs to a device which is configured as On, even when the system is in a power down mode.

COM Ports Accessed

When set to On (default), any event occurring at a COM (serial) port will awaken a system which has been powered down.

LPT Ports Accessed

When set to On (default), any event occurring at a LPT (printer) port will awaken a system which has been powered down.

Drive Ports Accessed

When set to On (default), any event occurring at a hard or floppy drive port will awaken a system which has been powered down.

IRQ1 (Keyboard)

When set to On (default), any event occurring at the keyboard will awaken a system which has been powered down.

The following is a list of IRQ's, Interrupt ReQuests, which can be exempted much as the COM ports and LPT ports above can. When an I/O device wants to gain the attention of the operating system, it signals this by causing an IRQ to occur. When the operating system is ready to respond to the request, it interrupts itself and performs the service.

As above, the choices are On and Off. Off is the default.

When set On, activity will neither prevent the system from going into a power management mode nor awaken it.

PCI Configuration Setup

This section describes configuring the PCI bus system. PCI, or Personal Computer Interconnect, is a system which allows I/O devices to operate at speeds nearing the speed the CPU itself uses when communicating with its own special components. This section covers some very technical items and it is strongly recommended that only experienced users should make any changes to the default settings.

PCI Slot Configuration

Slot x Using INT#

Some PCI devices use interrupts to signal that they need to use the PCI bus. Some devices, notably most graphics adapters, may not need an interrupt service at all. Each PCI slot is capable of activating up to four interrupts, INT# A, INT# B, INT# C and INT# D. By default, a PCI slot is allowed INT# A. Assigning INT# B has no meaning unless the device in the slot requires two interrupt services rather than just one. Likewise, using INT# C can only mean the device requires three interrupts and similarily for INT# D.

Selecting the default, AUTO, allows the PCI controller to automatically allocate the interrupts.

1st/2nd/3rd/4th Available IRQ

A INT# is an interrupt request which is signaled to and handled by the PCI bus. However, since the operating system usually has the final responsibility for handling I/O, INT#s can be mapped to an IRQ if the device occupying a given slot requires an IRQ service. By default, IRQ's 9 and 10 to PCI are mapped to PCI devices, but any available, unused IRQ can be used.

You can select which INT# is associated with each PCI slot and which conventional IRQ is associated with one of the two available INT#s. The IRQ settings must be the same as the jumper settings on the motherboard.

A setting of NA means the IRQ has been assigned to the ISA bus and is not available to any PCI slot.

PCI IRQ Activated by

This sets the method by which the PCI bus recognizes that an IRQ service is being requested by a device. Under all circumstances, you should retain the default configuration unless advised otherwise by your system's manufacturer.

Choices are Level (default) and Edge.

PCI IDE IRQ Map to

This allows you to configure your system to the type of IDE disk controller in use. By default, Setup assumes that your controller is an ISA (Industry Standard Architecture) device rather than a PCI controller. The more apparent difference is the type of slot being used.

If you have equipped your system with a PCI controller, changing this allows you to specify which slot has the controller and which PCI interrupt (A, B,C or D) is associated with the connected hard drives.

Remember that this setting refers to the hard disk drive itself, rather than individual partitions. Since each IDE controller supports two separate hard drives, you can select the INT# for each. Again, you will note that the primary has a lower interrupt than the secondary as described in "Slot x Using INT#" above.

Selecting "PCI Auto" allows the system to automatically determine how your IDE disk system is configured.