active at a time. A special cable or adapter is needed to convert the latter port to a standard DA-15 connector. There are also two Basic Rate Interface (BRI) ISDN connectors; the system shipped with plastic blocking plugs inserted in these connectors. Additional SBus network cards can also be added. Graphics support Most SPARCstation 10 systems lack integrated graphics. A very few, referred to as the SPARCstation 10SX, include the SX, or CG14, framebuffer used on the SPARCstation 20, requiring a 4 MB or 8 MB VSIMM to operate. All SPARCstation 10s seem to have the VSIMM slots, a cutout in the case and solder pads for the SX's 13W3 connector. Other options include the CG6 (GX, GX+, Turbo GX and TGX+) 8-bit SBus framebuffers, capable of up to 1280×1024 resolution in 8-bit color, and the ZX (Leo). The ZX is a 24-bit card with hardware-accelerated 3D operations, offering high speeds and resolutions, however, it's poorly supported, takes up two SBus slots, and runs extremely hot. Its faster cousin, the Turbo ZX, requires a fan card, taking up all four SBus slots. Full support is only available in Solaris 2.4 through 2.6, though the 2.6 drivers can be made to work in Solaris 7, 8 and 9. Linux includes an accelerated driver for it which supports 2D acceleration features, but no 3D. NetBSD and OpenBSD support it, but without acceleration, while NeXTSTEP and OPENSTEP have no support whatsoever. NVRAM The SPARCstation 10 uses a battery-backed NVRAM module to hold data about the system, such as the host ID (serial number) and MAC address. If the battery on the chip dies, then the NVRAM module must be replaced (or modified to use an external battery), and the NVRAM must be reprogrammed with a MAC address and host ID. Optionally a M48T08-100PC1 can be used. Operating systems SunOS 4.1.3 onwards Solaris (Solaris 2.1 to 9; Solaris 10 dropped support for 32-bit SPARC systems.) Linux NetBSD/SPARC OpenBSD/sparc32 - All versions up to 5.9 (OpenBSD 5.9 was the last release to support SPARC32) NeXTSTEP (SuperSPARC CPU modules only) OPENSTEP/Mach (SuperSPARC CPU modules only) Related computers SPARCstation 20 See also SPARCstation References External links SPARCstation 10 Handbook The Rough Guide to MBus Modules - SPARCStation 10 http://sunstuff.org/hardware/systems/sun4/ http://www.obsolyte.com/sun_ss10/ Sun workstations SPARC microprocessor products