In 1975, the first PC was made and since then, PC’s have become much more powerful. The first PC was created by IBM. Also, that was when the first motherboard was seen. Copper is used in motherboards as copper is not very reactive and can hold heat well. Copper only reacts when it is heated and is in contact with air/oxygen, which is why it is a preferred choice by manufacturers. Copper needs contact with air/oxygen so it can react the way it does as it is the only metal that reacts without water or dilute with acids. Motherboards heat up as they have many components connected onto them such as the RAM or the central processing unit(CPU). When that happens, the copper gets heated on the motherboard which causes all the components to work. Usually, a motherboard stays at 30-40°C, which is just enough that copper can react. Copper's melting point is more or less 1058°C of heat (onlinemetals.com). In the article “The Thermal and Electrical Conductivity of Copper at Low Temperatures” by R. Berman and D. K. C. MacDonald, it concluded that copper is less reactive when cold and more when heated{2}.
Another reason copper is used instead of any other metal is that copper is very cheap. For a pound of copper, it is USD$2.87 which would be much cheaper than Gold. Although there have been motherboards made with gold, they have been very expensive and they can’t even come close to the performance of a motherboard using Copper. Copper is more economically friendly for the manufacturers as prices usually go down for copper. This is good for the manufacturers and the consumers as motherboards can be produced at a cheaper price. If a motherboard has 1oz of copper, it will be slightly cheaper than a motherboard with 2 oz of copper.
Copper is also less denser than gold. Gold’s density is 19.32 g/cm³ while copper is 8.96 g/cm³. It is better to have a less dense material as it will make the weight of it lighter which means that when you mount it onto the case, it as a lesser likelihood of falling. The atomic mass of copper is significantly less as well. Copper’s atomic mass is 63.546 u whereas gold is 196.96657 u. This means that copper is much lighter than gold.
“The change in energy (in kJ/mole) of a neutral atom or molecule (in the gaseous phase) when an electron is added to the atom to form a negative ion” (www.nuclear-power.net/copper-affinity-electronegativity-ionization/) . The electron Affinity of Copper is 118.4 kJ/mol. The Electron Affinity of Gold is 222.8 kJ/mol. The most noticeable difference between these values is the huge difference between the numbers. The trend is across the periodic table and describes how much energy in an atom is released. This means that gold releases more energy than copper which is not good as you would not want you motherboard to produce too much energy{2}. This is another reason copper is used over gold.
Copper is cheap. The cost of copper is 2.87 USD for one pound. Most motherboards in laptops have 1 oz or 0.0625 pounds. Also, copper prices don’t rise a lot. Copper is good for thermals
Due to copper's melting point of 1058°C, it is used in motherboards as it can take a lot of heat from the different components connected to the motherboard. Also, if any part of the motherboard overheats, you can buy copper plates and use thermal paste and connect them on so the heat can be split to the copper which can hold all of it without a problem (How to Repair Laptop from Overheating with Copper Shims from Banggood). Also, copper is cheap which will benefit the producer as they can include more copper for better thermal performance and they can buy copper for cheap. If a manufacturer doesn’t include a lot of copper, it is possible to add more copper using thermal paste to the motherboard (The Weird and Wonderful Materials That Make up Your PC).
Since copper is mined from mines which are deep, copper is found in ores which need to be mined and then burned to get copper. That process alone takes a lot of time and can damage the environment. Also, since many other items are made with copper, we will soon run out of copper.