This section will walk you through pre-installation hardware setup, if any, that you will need to do prior to installing Debian. Generally, this involves checking and possibly changing firmware settings for your system. The ``firmware'' is the core software used by the hardware; it is most critically invoked during the bootstrap process (after power-up). Known hardware issues affecting the reliability of &debian; on your system are also highlighted. &bios-setup-i386.xml; &bios-setup-m68k.xml; &bios-setup-powerpc.xml; &bios-setup-sparc.xml; &bios-setup-s390.xml; Many people have tried operating their 90 MHz CPU at 100 MHz, etc. It sometimes works, but is sensitive to temperature and other factors and can actually damage your system. One of the authors of this document over-clocked his own system for a year, and then the system started aborting the gcc program with an unexpected signal while it was compiling the operating system kernel. Turning the CPU speed back down to its rated value solved the problem. The gcc compiler is often the first thing to die from bad memory modules (or other hardware problems that change data unpredictably) because it builds huge data structures that it traverses repeatedly. An error in these data structures will cause it to execute an illegal instruction or access a non-existent address. The symptom of this will be gcc dying from an unexpected signal. Atari TT RAM boards are notorious for RAM problems under Linux; if you encounter any strange problems, try running at least the kernel in ST-RAM. Amiga users may need to exclude RAM using a booter memfile. FIXME: more description of this needed. The very best motherboards support parity RAM and will actually tell you if your system has a single-bit error in RAM. Unfortunately, they don't have a way to fix the error, thus they generally crash immediately after they tell you about the bad RAM. Still, it's better to be told you have bad memory than to have it silently insert errors in your data. Thus, the best systems have motherboards that support parity and true-parity memory modules; see . If you do have true-parity RAM and your motherboard can handle it, be sure to enable any BIOS settings that cause the motherboard to interrupt on memory parity errors. Many systems have a turbo switch that controls the speed of the CPU. Select the high-speed setting. If your BIOS allows you to disable software control of the turbo switch (or software control of CPU speed), do so and lock the system in high-speed mode. We have one report that on a particular system, while Linux is auto-probing (looking for hardware devices) it can accidentally touch the software control for the turbo switch. Many users of Cyrix CPUs have had to disable the cache in their systems during installation, because the floppy disk has errors if they do not. If you have to do this, be sure to re-enable your cache when you are finished with installation, as the system runs much slower with the cache disabled. We don't think this is necessarily the fault of the Cyrix CPU. It may be something that Linux can work around. We'll continue to look into the problem. For the technically curious, we suspect a problem with the cache being invalid after a switch from 16-bit to 32-bit code. You may have to change some settings or jumpers on your computer's peripheral cards. Some cards have setup menus, while others rely on jumpers. This document cannot hope to provide complete information on every hardware device; what it hopes to provide is useful tips. If any cards provide ``mapped memory'', the memory should be mapped somewhere between 0xA0000 and 0xFFFFF (from 640K to just below 1 megabyte) or at an address at least 1 megabyte greater than the total amount of RAM in your system. If you have no AT-style keyboard and only a USB model, you will need to enable legacy AT keyboard emulation in your BIOS setup. Consult your main board manual and look in the BIOS for "Legacy keyboard emulation" or "USB keyboard support" options. It must be enabled in order to boot the installation system. If you enabled this option and it is working for you, you are fine and can go ahead. If you cannot find this option, it might be that it is always enabled and you can continue. It also might mean that the BIOS does not provide any emulation support (bad luck here). If you find the option and enable it, but the emulation stops working soon after the kernel started, then you have bad luck too. You could try the "bf2.4" flavor where the root floppy brings USB modules. If you are installing with floppy disks, you would need the keyboard once before the USB modules can be loaded. Specifying the "keytimer" option at boot prompt may help in this case. Sometimes, the emulation hangs but it wakes up after few minutes, so you could wait some time and try to continue. To fix this behavior, you could load Linux' own drivers for USB keyboards. For this, use "modconf" (Step "Configure Device Driver Modules") and load usb-uhci or usb-ohci modules. The Linux Kernel can not always detect what amount of RAM you have. If this is the case please look at .