Hsing Mother Board video prolems

[Goatimus]

My computer is only displaying in 16 bit mode and will only go to the the smallest settings (600x480) and i can't figure out how to get the setting to adjust to true color, i've tried the settings tab and it just dosn't work, it won't slide, i used everest to grab some info and this is some of what i got:
Computer:
Operating System Microsoft Windows 98
OS Service Pack -
Internet Explorer 5.00.2314.1003 (IE 5.0 - Office 2000)
DirectX 4.09.00.0902 (DirectX 9.0b)

Motherboard:
CPU Type AMD Duron, 800 MHz (8 x 100)
Motherboard Name PCChips M810LR (2 PCI, 1 AGP, 1 AMR, 2 DIMM, Audio, Video, LAN)
Motherboard Chipset SiS 730S
System Memory 119 MB (SDRAM)
BIOS Type AMI (12/28/00)
Communication Port Communications Port (COM1)
Communication Port Printer Port (LPT1)

Display:
Video Adapter Standard Display Adapter (VGA) (64 KB)
3D Accelerator SiS 300 Integrated
Monitor Plug and Play Monitor [NoDB] (8182)

Multimedia:
Audio Adapter MPU-401-compatible
Audio Adapter SiS 7018 Audio Accelerator

Storage:
IDE Controller Primary IDE controller (dual fifo)
IDE Controller Secondary IDE controller (dual fifo)
IDE Controller SiS 5513 Dual PCI IDE Controller
SCSI/RAID Controller Iomega Clik! Parallel Port Interface
SCSI/RAID Controller Iomega Parallel Port Zip Interface
SCSI/RAID Controller SiS USB Open Host Controller
SCSI/RAID Controller SiS USB Open Host Controller
Rendering Subsystem
USB1 Controller SiS 7001 PCI-USB Open Host Controller
USB1 Controller SiS 7001 PCI-USB Open Host Controller

can anyone help me?