Computer power supplies are switching power supplies that can handle small (~20V) variations in power automatically. Newer computer power supplies that are high efficiency (Active PFC) may even have a wider operating range.

That said, when the AC mains (line) power is outside (above or below) the standard range, the power supply may fail to deliver the right voltages (Volts) at the necessary or expected current (Amps or Amperes) levels. If the power supply fails such that it delivers either too high a voltage or current, this may damage the components in the computer, including low voltage, "high" current devices such as the CPU and RAM.

Here are two short articles about how overvoltage may damage components. Why does too much heat/voltage damage the CPU? from Overclockers, and Overvolted RAM May Kill Your Core i7 CPU from Tom's Hardware. Though they are oriented to overclocking, the damage is the same (that's a discrete transistor, CPU transistors are much smaller).

As far as software / data -level damage, this can be reduced (mitigated) but not eliminated by use of more advanced file systems that support journaling.

Two devices that are related but do not replace an UPS are:

• Surge Protector (and how they work)
• Line or Power Conditioner

These devices are generally simpler and thus less expensive than an UPS.

That said, I personally and professionally always try to use UPSes to protect the computers I use. The cost of a good UPS is about 10-20% of a mid-range desktop system, but a decent UPS with replacement batteries can last 10+ years of services so the cost it amortized over quite a numbers of years, and in my own personal (and professional) experiences every single UPS I have bought has paid for themselves either in cost savings in terms of preventing premature hardware failure, or in terms of cost of preventing data loss.

The batteries do need to be replaced 3-5 years depending on circumstances (frequency of battery usage, battery chemistry, avg/peak temperature, discharge amount), but are $40-50 per UPS for an average mid-range system suitable for a home or office desktop system.

I tend to view UPS like anti-virus, they are a "best practices" or simply good computer hygiene, that help to prevent costly failures.

Computer power supplies are switching power supplies that can handle small (~20V) variations in power automatically. Newer computer power supplies that are high efficiency (Active PFC) may even have a wider operating range.

That said, when the AC mains (line) power is outside (above or below) the standard range, the power supply may fail to deliver the right voltages (Volts) at the necessary or expected current (Amps or Amperes) levels. If the power supply fails such that it delivers either too high a voltage or current, this may damage the components in the computer, including low voltage, "high" current devices such as the CPU and RAM.

Here are two short articles about how overvoltage may damage components. Why does too much heat/voltage damage the CPU? from Overclockers, and Overvolted RAM May Kill Your Core i7 CPU from Tom's Hardware. Though they are oriented to overclocking, the damage is the same (that's a discrete transistor, CPU transistors are much smaller).

As far as software / data -level damage, this can be reduced (mitigated) but not eliminated by use of more advanced file systems that support journaling and backup files / file systems.

Two devices that are related but do not replace an UPS are:

• Surge Protector (and how they work)
• Line or Power Conditioner

These devices are generally simpler and thus less expensive than an UPS.

That said, I personally and professionally always try to use UPSes to protect the computers I use. The cost of a good UPS is about 10-20% of a mid-range desktop system, but a decent UPS with replacement batteries can last 10+ years of services so the cost it amortized over quite a numbers of years, and in my own personal (and professional) experiences every single UPS I have bought has paid for themselves either in cost savings in terms of preventing premature hardware failure, or in terms of cost of preventing data loss.

The batteries do need to be replaced 3-5 years depending on circumstances (frequency of battery usage, battery chemistry, avg/peak temperature, discharge amount), but are $40-50 per UPS for an average mid-range system suitable for a home or office desktop system.

I tend to view UPS like anti-virus, they are a "best practices" or simply good computer hygiene, that help to prevent costly failures.

Computer power supplies are switching power supplies that can handle small (~20V) variations in power automatically. Newer computer power supplies that are high efficiency (Active PFC) may even have a wider operating range.

That said, when the AC mains (line) power is outside (above or below) the standard range, the power supply may fail to deliver the right voltages (Volts) at the necessary or expected current (Amps or Amperes) levels. If the power supply fails such that it delivers either too high a voltage or current, this may damage the components in the computer, including low voltage, "high" current devices such as the CPU and RAM.

Here are two short articles about how overvoltage may damnage components. Why does too much heat/voltage damage the CPU? from Overclockers, and Overvolted RAM May Kill Your Core i7 CPU from Tom's Hardware. Though they are oriented to overclocking, the damage is the same (that's a discrete transistor, CPU transistors are much smaller).

As far as software / data -level damage, this can be reduced (mitigated) but not eliminated by use of more advanced file systems that support journaling.

Two devices that are related but do not replace an UPS are:

• Surge Protector (and how they work)
• Line or Power Conditioner

These devices are generally simpler and thus less expensive than an UPS.

That said, I personally and professionally always try to use UPSes to protect the computers I use. The cost of a good UPS is about 10-20% of a mid-range desktop system, but a decent UPS with replacement batteries can last 10+ years of services so the cost it amortized over quite a numbers of years, and in my own personal (and professional) experiences every single UPS I have bought has paid for themselves either in cost savings in terms of preventing premature hardware failure, or in terms of cost of preventing data loss.

The batteries do need to be replaced 3-5 years depending on circumstances (frequency of battery usage, battery chemistry, avg/peak temperature, discharge amount), but are $40-50 per UPS for an average mid-range system suitable for a home or office desktop system.

I tend to view UPS like anti-virus, they are a "best practices" or simply good computer hygiene, that help to prevent costly failures.

Computer power supplies are switching power supplies that can handle small (~20V) variations in power automatically. Newer computer power supplies that are high efficiency (Active PFC) may even have a wider operating range.

That said, when the AC mains (line) power is outside (above or below) the standard range, the power supply may fail to deliver the right voltages (Volts) at the necessary or expected current (Amps or Amperes) levels. If the power supply fails such that it delivers either too high a voltage or current, this may damage the components in the computer, including low voltage, "high" current devices such as the CPU and RAM.

Here are two short articles about how overvoltage may damage components. Why does too much heat/voltage damage the CPU? from Overclockers, and Overvolted RAM May Kill Your Core i7 CPU from Tom's Hardware. Though they are oriented to overclocking, the damage is the same (that's a discrete transistor, CPU transistors are much smaller).

As far as software / data -level damage, this can be reduced (mitigated) but not eliminated by use of more advanced file systems that support journaling.

Two devices that are related but do not replace an UPS are:

• Surge Protector (and how they work)
• Line or Power Conditioner

These devices are generally simpler and thus less expensive than an UPS.

That said, I personally and professionally always try to use UPSes to protect the computers I use. The cost of a good UPS is about 10-20% of a mid-range desktop system, but a decent UPS with replacement batteries can last 10+ years of services so the cost it amortized over quite a numbers of years, and in my own personal (and professional) experiences every single UPS I have bought has paid for themselves either in cost savings in terms of preventing premature hardware failure, or in terms of cost of preventing data loss.

The batteries do need to be replaced 3-5 years depending on circumstances (frequency of battery usage, battery chemistry, avg/peak temperature, discharge amount), but are $40-50 per UPS for an average mid-range system suitable for a home or office desktop system.

I tend to view UPS like anti-virus, they are a "best practices" or simply good computer hygiene, that help to prevent costly failures.