User`s guide

Frequently Asked Question
B-5
DMA mode 1 30ns 5 150ns (1/150ns) x 2byte =
13.3MB/s
DMA mode 2 30ns 4 120ns (1/120ns) x 2byte =
16.6MB/s
DMA/33 30ns 4 120ns (1/120ns) x 2byte x2 =
33MB/s
Q: What is the performance of Ultra DMA/33? Do we need special driver?
A: Currently (Jan 1997), the only Ultra DMA/33 HDD we can test is Quantum 1620AT. It is only a lab
pilot run sample and has not been tuned to best performance. The final sample will probably be ready
in the middle of Feb. You need driver to activate DMA/33, there are now driver from INTEL or you can
use driver in the Windows 95 Memphis, which can recognize South Bridge PIIX4.
Model OS/Driver Mode Winbench96
Diskwinmark
Quantum
1620AT
Windows 95
OSR2
PIO mode 4 1330
Quantum
1620AT
Windows 95
OSR2
DMA mode 2 1300
Quantum
1620AT
Windows 95
OSR2 + INTEL
driver
DMA/33 1280
Quantum
1620AT
Windows 95
Memphis
PIO mode 4 1280
Quantum
1620AT
Windows 95
Memphis
DMA/33 1330
Q: What is PnP (Plug and Play)?
A: In the past, the IRQ/DMA and memory or I/O space of add-on cards are normally set manually, i.e.,
by jumper or by proprietary utility. The user has to check the user's guide for the correct setting.
Sometimes, resource conflict occurs and this leads to unstable system.. The PnP specification
suggests a standard register interface for both BIOS and OS (such as Win95). These registers are
used by BIOS and OS to configure system resource and prevent any conflicts. The
IRQ/DMA/Memory will be automatically allocated by PnP BIOS or OS.
Currently, almost all the PCI cards and most ISA cards are PnP compliant. If you are still using a
Legacy ISA card that cannot support PnP, set the corresponding resource (IRQ/DMA/memory) to
ISA in the BIOS "PCI/PnP Setup".
Q: What is ACPI (Advanced Configuration & Power Interface) and OnNow?
A: The ACPI is new power management specification of 1997 (PC97). It intends to save more power by
taking full control of power management to operating system and not through BIOS. Because of this,
the chipset or super I/O chip needs to provide standard register interface to OS (such as Win97) and
provides the ability for OS to shutdown and resume power of different part of chip. The idea is a bit
similar to the PnP register interface.
ACPI defines momentary soft power switch to control the power state transition. Most likely, it uses
the ATX form factor with momentary soft power switch. The most attractive part of ACPI for desktop
user is probably the "OnNow" feature, an idea from notebook. This feature allows you to immediately
resume to your original work without the long time waiting from bootup, entering Win95 and running
Winword. The AX5T with Intel TX chipset can support ACPI.