BIOS Setup

Advanced Chipset Setup (Cont.)

Today we will discuss other important options available in the advanced machine setup. The options below increase the PC performance when enabled, therefore we suggest you enable them. However not all PCs are fully compatible with those options, and some PCs may not boot after having enabled some of them. If that happens, one must disable the option that is causing the problem.

• CPU Burst Write or CPU-to-Memory Burst Write: Increases the write to RAM performance.
• PCI Bursting or Host-to-PCI Burst Write or PCI Burst Mode or PCI Burst Write Combine or PCI Dynamic Bursting: Enables PCI burst mode, increasing the PCI bus performance.
• PCI Concurrency or Peer Concurrency: Allows the PCI bus controlling more than one PCI device at a time, increasing the performance.
• PCI Streaming: Allows the transfer of larger data packets, increasing the PCI bus performance.
• PCI-to-DRAM Pipeline: Increases data write performance done by PCI bus to RAM.
• CPU-to-PCI Write Post or CPU-to-PCI Write Buffer: Enables a buffer memory to temporarily store data sent by the processor to PCI bus, in case the bus is not ready, thus freeing the processor for the execution of another task. If this option is disabled, the processor will have to wait for the bus to become ready to receive data, decreasing the write performance of PCI bus.
• PCI Master 0 WS Write: Allows that PCI devices write in RAM without using wait states.
• Passive Release: Increases the PCI bus performance.

Below are some other options available in the advanced setup:

• PCI IRAQ Activated By: Sets whether PCI bus interruptions are triggered by edge or level of the interrupt request signal. We suggest you set it at “level”.
• Delay Transaction or PCI 2.1 Support: If enabled, motherboard chipset will be compliant with PCI 2.1 specifications. We suggest to enable.
• AT Bus Clock or AT Clock Selection or Bus Clock Frequency Select or ISA Bus Clock Option or AR Bus Clock Control or PCICLK-to-ISA Sysclk Divisor: This option sets the ISA bus clock which should run at 8 MHz. As most motherboards are not equipped with an internal 8 MHz generator, they will use a division of the Bus Clock or of the bus clock (PCICLK). If the PCI bus clock runs at 33 MHz, we must set up this option at “1/4 PCICLK” that will set up the ISA bus clock at 8.25 MHz. You can do this calculation yourself to determine the best setup for this option. We recall that ISA devices usually cannot run much above 8 MHz. Therefore if you set up this option at a higher clock frequency, i.e., 11 MHz, your PC ISA devices probably will not operate properly.