Hardware Reference
In-Depth Information
USB 2.0 device in a USB 1.1 port or a PCIe 16x display adapter in a system that doesn't have
an available PCIe 16x slot. Power-connection incompatibilities can also occur, such as when
you need to connect a SATA device but your power supply has no free SATA power-supply
connectors.
Incompatible or insuffi cient hardware can result in failures of various types. Here are
some examples:
A USB hub, in theory, can support dozens of devices. However, if many of those
devices are unpowered (that is, they rely on drawing the power they need from the
USB port without a separate power supply), a USB hub can reach its maximum power
output quickly, and some of the devices may not receive enough power. Your OS may
warn you that that's what's going on or some of the devices may simply stop working.
Your PC's power supply can also become overloaded if you have many devices installed
that draw lots of power. For example, if you have three full-size mechanical hard drives
in a system with a cheap power supply, installing a fourth drive may cause problems at
startup because there isn't enough power to allow all four drives to spin up at once.
A new device may not show up in the OS until you install the device driver for it.
Further, when you install a new device driver, that driver may be incompatible with
some other driver already installed, or it may overwrite system fi les that some other
application or device needs.
Although this rarely occurs anymore, on some older versions of Windows device-
resource confl icts may still occur where Windows assigns the same resources to multiple
devices. System resources include things like I/O addresses, memory addresses, and
Interrupt Request lines (IRQs). You can troubleshoot such problems in the Device
Manager by manually assigning resources to a device so that it no longer confl icts with
other devices. That type of confi guration is beyond the scope of this topic.
Installing Upgrades
Next, let's get down to the nitty-gritty and talk about the procedures for physically
installing upgrade components.
Safety Considerations
Computers aren't very dangerous; you generally have to work pretty hard to hurt yourself
while working on one. Here are some safety tips:
Wear short sleeves, or roll up your sleeves, so you don't get a sleeve caught on a sharp
corner and rip it.
Remove jewelry, especially dangling earrings and neck chains, so you don't catch them
on anything that may be sticking out.
