BIOS Setup | Hardware Secrets

Floppy Disk Access Control: This options configures if user has total access to floppy unit (Read/Write option) or if he is allowed only to reading them (Read Only option). Set up R/W unless there is a specific case where you don't want to allow floppy disks recording.
HDD Sequence SCSI/IDE First: If you have an IDE hard disk and a SCSI disk installed simultaneously in the computer, you'll need to configure, by means of this option which will boot. If you don't have a SCSI disk, leave this option as "IDE". Or set it up according to your needs.
Assign IRQ for VGA: This option forces the utilization of an interruption request line by the video board. If this option is disabled, video board will not use an IRQ, freeing the space to be used by another peripheral device, which may be convenient in some cases, as is the case of computers plenty of peripheral devices creating interrupt request conflicts with the video board. Though this may seems interesting, DOS programs and particularly games will not be able to access video with more than 256 colors if this option is disabled. Therefore, we suggest you leave this option enabled. Furthermore this is the solution of the classic case you're not succeeding in setting up more than 256 colors in your favorite game.
Init Display First: If you have more than one video board installed, in order to make use of the Windows 98 multiple displays support, and if one them if an AGP, you'll have to set which video board will initiate first by means of this option. the AGP board or the PCI one. You must adjust this option according to your personal preferences. In computers having an on-board video card, this option can be used to disable on-board video, installing a PCI video board and setting this option as PCI. In case you don't have more than one video board this option is ignored.
BIOS Update: This option enables BIOS upgrade. There is a famous virus, called CIH (better known as Spacefiller or Chernobyl) that erases BIOS. If this option is disabled, BIOS upgrade is not possible, and this virus will not be able to erase BIOS, in case computer gets infected. Our suggestion is that you disable this option and enable it only during BIOS upgrade procedure (this procedure is seldom needed for most users).
Report No FDD For Win95: Enable this option only if you don't have any floppy unit installed. Naturally this option must stay disabled.
Delay for HDD: Very old hard disks take a while to reach their normal rotating speed. The most common symptom of this problem is the "HDD Controller Failure" error message being displayed at power on but functioning correctly after a reset. This happens because at the first time computer tried to boot, the disk had not reached full rotation speed, causing the display of the error message. If this is the case, you may set up a waiting time - in seconds - that will be timed after memory counting until start of hard disk reading. As this problem can only be found in old hard disks, let this option disabled - or in zero.
S.M.A.R.T. For Hard Disks: Enables Self-Monitoring, Analysis and Report Technology - SMART - for the hard disk, in case it has this technology (all new hard disks have it). It is a preventive internal diagnostic facility that is performed by hard disk informing to processor the probability of a possible damage in a near future, thus giving time for the user to backup his data before damage occurs. We recommend you enable this option.
Graphics Aperture Size: AGP video boards can use RAM memory to store z-buffering and texture data. This option defines how much RAM these video boards can use for themselves. Generally you may leave this option setup with its default, but you may try to change this value in case you're getting errors in 3D games.
CPU Level 2 Cache ECC Checking: Intel processors from Pentium II-300 onwards allow the utilization of an advanced error correction mode when accessing L2 cache memory, called ECC (Error Correction Code). This access method increases data reliability. Though it may seems interesting to enable this option, it decreases computer performance, as computer will spend more time storing and reading memory cache data because of this error verification. Therefore our suggestion is that you leave this option disabled.
System BIOS Cacheable or System ROM Cacheable or System BIOS Shadow Cacheable: This option enables the utilization of memory cache when access BIOS. As BIOS is accessed all times and as the memory cache increases computer performance, this option will also increase computer performance. Therefore we suggest this option stays enabled.
Video BIOS Cacheable or Video Cacheable Option or Video ROM Cache: This option is equivalent to previous option except for the video board ROM memory. We suggest this option stays enabled improving video performance.