Instruction Set Essays - IBM PC Compatibles, Computer Enclosure

Instruction Set Essays - IBM PC Compatibles, Computer Enclosure Instruction Set It has become increasingly popular to build one's own computer. In many cases, it saves money, and guarantees that you get what you want. Building your own computer also assures that you avoid the proprietary designs many companies use to utilize to keep the customers coming back for new parts. Most importantly, having built the system, you become very familiar with your system and with computers in general. There is no reason not to tackle the project of building your own computer. A very basic knowledge is required, and you can learn as you go! Materials and Tools Needed Upon having researched the quality of the parts you want to use to build your computer, you will need the following basic items to assemble your processor: Case/Tower Motherboard CPU (central processing unit) Heat sink and fan Floppy drive Hard drive and CD-ROM Video card (optional but very recommended) The accessories needed to put together your processor should come with each of the components purchased. However, the basic screws that will be required are the following: Chassis screws Smaller screws (these are just like the chassis screws, but have a smaller diameter) Standoffs Washers Spacers (snap-in and standard) There are a variety of different tools you may need while building your system. Here are a few of the most common ones: Flat head screwdriver Magnetized Phillips head screwdriver Regular Phillips head screwdriver The entire installation process of the components should take approximately an hour, but this all depends on the level of experience and knowledge of the builder. Precautions and warnings There are a few things that you should be aware of when you are building your computer so you don't hurt yourself or damage any of the components. Wash and dry your hands Make sure you ground yourself by touching an uncoated part of your computer's chassis prior to touching any of the components. It is recommended to wear the anti-static strap. Be careful of sharp edges within your case Only handle PCB's (your motherboard, video card, etc) from the edges whenever possible. Touching the contacts can damage them. Avoid using magnetic screwdrivers when installing your hard drive, since it is a magnetic storage medium. In the following pages, you will find the instruction steps to preparing, installing and testing your new processor Preparation At this point, have the new case in front of you with the cover removed. Before any installation of the components takes place, you must prepare it for use. Go through the following checklist to ensure it is prepared. 1. Clean the case. Clean out the inside with a rag and compressed air to ensure the case is free of dust. 2. Inspect the power supply. Make sure it is set to the proper voltage (110V). 3. Install feet. These are tabs inserted into the holes at the bottom of the case. 4. Install the case fan. Screw the fan onto a rack next to the vent on the front of the case with the accompanying screws. INSTALLATION PROCESS Installing the CPU CAUTION: Installing the CPU is straight forward, but doing this step too fast or carelessly can result in damage to the processor. 5. Install the processor rack into Slot 1 (a PCI slot) of the motherboard, which is a support for the CPU to rest in. 6. Position a rail on each end of the Slot. Use the small screws on each end of the slot to tighten it into place onto the motherboard. 7. Insert the Processor into the Slot. Push the processor into the guide rails and down all the way to the surface of the slot. Installing the Heat Sink Now that the CPU is installed in the motherboard, the installation of the heat sink and fan are required. 8. Attach the fan to the heat sink using the four screws provided with the CPU fan. 9. Apply the heat sink compound to cover surface of the chip. 10. Attach the heat sink on top of the processor, pressing down lightly. 11. Make sure all areas of the chip are in contact with the heat sink. Wipe off any excess of the compound that may have oozed out the sides. Installing the Memory Installing the memory modules, otherwise known as SIMMS or DIMMS are placed in the memory slots of the motherboard. 12. Install the memory module (SIMM

Hemophilia in Queen Victoria’s Descendants

Hemophilia in Queen Victoria’s Descendants Three or four of the children of Queen Victoria and Prince Albert are known to have had the hemophilia gene.  A son, four grandsons, and six or seven great-grandsons and possibly a great-granddaughter were afflicted with hemophilia. Two or three daughters and four granddaughters were carriers who passed the gene to the next generation, without themselves being afflicted with the disorder. How Inheriting Hemophilia Work Hemophilia  is a chromosome disorder which is located on the sex-linked X chromosome.  The trait is recessive, which means that women, with two X chromosomes, must inherit it from both mother and father for the disorder to appear.  Men, however, have only one X chromosome, inherited from the mother, and the Y chromosome all men inherit from the father does not protect the male child from manifesting the disorder. If a mother is a carrier of the gene (one of her two X chromosomes has the abnormality) and the father is not, as seems to have been the case with Victoria and Albert, their sons have a 50/50 chance of inheriting the gene and being active hemophiliacs, and their daughters have a 50/50 chance of inheriting the gene and being a carrier, also passing it along to half of their children. The gene can also appear spontaneously as a mutation on an X chromosome, without the gene being present in the X chromosomes of either father or mother. Where Did the Hemophilia Gene Come From? Queen Victoria’s mother, Victoria, Duchess of Kent, did not pass a hemophilia gene to her older son from her first marriage, nor did her daughter from that marriage seem to have the gene to pass down to her offspring - the daughter, Feodora, had three sons and three daughters.  Queen Victoria’s father, Prince Edward, Duke of Kent, did not show signs of hemophilia.  There is a small possibility that the Duchess had a lover who had survived to adulthood though afflicted with hemophilia, it would have been highly unlikely that a man with hemophilia would have survived to adulthood at that time in history.  Prince Albert showed no signs of the disease, so he’s unlikely to have been the source of the gene, and not all the daughters of Albert and Victoria seem to have inherited the gene, which would have been true if Albert had the gene. The assumption from the evidence is that the disorder was a spontaneous mutation either in her mother at the time of the queen’s conception, or, more likely, in Queen Victoria. Which of Queen Victoria’s Children Had the Hemophilia Gene? Of Victoria’s four sons, only the youngest inherited hemophilia.  Of Victoria’s five daughters, two definitely were carriers, one was not, one had no children so it is not known whether she had the gene, and one may or may not have been a carrier. Victoria, Princess Royal, German Empress and Queen of Prussia: her sons showed no signs of being afflicted, and none of her daughters’ descendants were, either, so she apparently did not inherit the gene.Edward VII: he was not a hemophiliac, so he did not inherit the gene from his mother.Alice, Grand Duchess of Hesse: she definitely carried the gene and passed it to three of her children.  Her fourth child and only son, Friedrich, was afflicted and died before he was three.  Of her four daughters who lived to adulthood, Elizabeth died childless, Victoria (maternal grandmother of Prince Philip) was apparently not a carrier, and Irene and Alix had sons who were hemophiliacs.  Alix, known later as Empress Alexandra of Russia, passed the gene to her son, the Tsarevitch Alexei, and his affliction influenced the course of Russian history.Alfred, Duke of Saxe-Coburg and Gotha: he was not a hemophiliac, so he did not inherit the gene from his mother.Princess Helena: she had two sons who died in infancy, which might be attributed to hemophilia, but that is not certain. Her other two sons showed no signs, and her two daughters did not have children. Princess Louise, Duchess of Argyll: she had no children, so there is no way to know if she had inherited the gene.Prince Arthur, Duke of Connaught: he was not a hemophiliac, so he did not inherit the gene from his mother.Prince Leopold, Duke of Albany: he was a hemophiliac who died after two years of marriage when bleeding could not be stopped after he fell. His daughter Princess Alice was a carrier, passing the gene to her eldest son who died when he bled to death after an automobile accident.  Alice’s younger son died in infancy so may or may not have been afflicted, and her daughter seems to have escaped the gene, as none of her descendants have been afflicted.  Leopold’s son, of course, did not have the disease, as sons do not inherit a father’s X chromosome.Princess Beatrice: like her sister Alice, she definitely carried the gene.  Two or three of her four children had the gene.  Her son Leopold bled to death during a knee operation at 32. Her son Ma urice was killed in action in World War I, and it’s disputed whether hemophilia was the cause. Beatrice’s daughter, Victoria Eugenia, married King Alfonso XIII of Spain, and their two sons both bled to death after car accidents, one at 31, one at 19.  Victoria Eugenia and Alfonso’s daughters have no descendants who’ve shown signs of the condition.