Overclocking

[Wardawg1001]

I'm kind of a noob at computer hardware and what not, I've heard of overclocking hundreds of times and I understand that it increases the speed the processor works at. I have a couple nagging questions though that I've never been able to get an answer for.

1. What exactly are you changing by overclocking your processor? What are you doing to make it run faster?

2. Why is overclocking possible? Why don't processors come out of the factory overclocked? It seems to make sense since manufacturers and retailers could sell the same hardware to uninformed customers for a higher price because they can advertise it as better hardware.

Obviously I'm missing something here, would appreciate it if someone would fill me in on the details, thanks.

 

[F1shF4t]

Originally posted by: Wardawg1001
I'm kind of a noob at computer hardware and what not, I've heard of overclocking hundreds of times and I understand that it increases the speed the processor works at. I have a couple nagging questions though that I've never been able to get an answer for.

1. What exactly are you changing by overclocking your processor? What are you doing to make it run faster?

2. Why is overclocking possible? Why don't processors come out of the factory overclocked? It seems to make sense since manufacturers and retailers could sell the same hardware to uninformed customers for a higher price because they can advertise it as better hardware.

Obviously I'm missing something here, would appreciate it if someone would fill me in on the details, thanks.

1. Essentially you are increasing the clock speed that the cpu is running at, increasing switching of the gates and the throughput etc. For example explaining in term of a car, a car in the same gear will go faster at 3000 rpm than at 2000rpm.

2. No overclock is guaranteed, each chip will overclock differently. Only a few times over the years have massive overclocks been possible to most users without exotic cooling. Manufacturers find the speed grades that most chips make, some can run faster, which is what we take advantage of.

Sale of overclocked chip has been done before, its illegal anyways.

 

[CTho9305]

2. Why is overclocking possible? Why don't processors come out of the factory overclocked? It seems to make sense since manufacturers and retailers could sell the same hardware to uninformed customers for a higher price because they can advertise it as better hardware.

When the manufacturer rates a processor at a particular speed, it has to be able to operate correctly at that speed for multiple years in worst-case conditions (highest-allowed temperature, lowest-allowed voltage). It also has to operate within a given thermal budget (e.g. 65W), which sets the cost of the cooling solution that OEMs (HP, Dell, etc) will have to use. When you overclock, you're operating in better-than-worst-case conditions: a fancy expensive cooler in an airconditioned building, possibly with higher voltages. You're also taking advantage of the fact that CPUs slow down as they age and you're operating them faster when they're young, often throwing them out before they're very old. When you overclock, you're also probably raising the power consumption, and the manufacturer may not want to sell 150W CPUs even if some overclockers are willing to use them (partly because OEMs don't want to spend much money on heatsinks, and they're a much bigger market).

The other reason you can overclock is that the CPU might not actually work properly at the speed you set it to, but you're just not running any tests that show obvious faults (this is why sometimes a new program will come out and OCers will find that their "rock solid" systems crash on the new test - e.g. LINPACK). This is a large part of why I don't overclock anymore - if I try out something new, like Google Chrome on this processor-intensive web page and it crashes, I don't want to wonder whether Google Chrome is about to replace LINPACK as the next favored overclocking stress test or if Chrome just has a bug that makes it crash there (this is just a hypothetical example... Chrome handles that page just fine). I used to have the patience to worry about that kind of stuff, but nowadays I'll trade a few percent of performance for more stability/reliability.

 

[Markfw]

CTho9305, wow, that's a great explanation, that I never thought of, and some of which I didn't know.

Regardless, great post !

Kudos !