# Understanding The Physics of Overclocking



## SwanSword (Aug 18, 2011)

I read through quite a bit of the overclocking guides, and the methods lack overall concept. It's like trying to learn a language one word at a time. But there are a few guidelines that will greatly increase air-cooled overclockability and decrease freezes, reboots, BSOD, and other annoying errors.

When you first build a machine, the components have seen very little use, primarily just brief testing. The chemistry and physics of a modern microprocessor is like a complicated ancient processor. The theory of operation hasn't changed much. 

The processor must be broken in first. With a new processor, you want to actually fully open and 'season' all the logic gates in the CPU. The most effective means to accomplish this is to load the level 2 cache suchwise that it will never access ram.

A program called mprime will do this. The level 1 cache accesses the level 2 cache, but the level two cache contains all code necessary to access all of the cpu, and very fast. 

This actually arranges the atoms in the processor, kind of like wearing trails through the woods, and it acclimates and trims the silicon doping of the 'transistors' to avert random bit errors for the life of the processor. 

You don't need to break in the processor immediately after the hardware is assembled, but you should run mprime on the stress setting for 24 hrs or so. There is also nothing that will heat a processor like mprime. 

I've had machines exhausting air that burned my hand. You also want the thermal compound to cure in the heat.

Memory is millions and billions of capacitors that look like buckets. Before any capacitor will respond properly, it must be 'formed'. So, as with the processor, you want to repeatedly access every part of the memory, in a way that is most difficult for the ram to relax.

Memtest86+ will access all the memory, in many different patterns, thereby forming the capacitors. This greatly increases memory bandwidth (MB/s). The great thing is: memtest86+ also reports all bits that did not hold the value placed there. 

Here's and example: in one of the memory exercises, memtest86+ sets every bit, but one at a time, and then cycles the 8 bits directly adjacent. But the main thrust is that every part of the memory is accessed billions of times. Benchmarks do not access every square angstrom of ram. 

You can do the ram formation about once a year. One footnote: overclocking memory manufacturers pay a large premium to ram chip makers for the privilege of 'hand picking' only the best chips. 

If you look at ram chip specs, they are all low performance. High performance ram manufacturers place the chip manufacturers specs in the spd, but advertise timings that are overclocked to begin with. 

Once you get the cpu and ram broken in, sometimes the machine won't even post unless the system is overclocked. And, when you find the sweet spot, and after the novelty wears off, you'll probably just want the machine to work. 

You might be tempted to mess with bios setup program timings and voltage, but there are other things in life too! So you leave it alone. If the bios setup values are pretty overclocked, and you leave them that way for years, the machine becomes those settings, and it won't work with the defaults anymore.

It's like if you made a face and kept it that way for years, it would be stuck like that. Overclocking is a blast, but it doesn't work with the Linux kernel very well. Microsoft designs Windows partially for overclockers.


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## Johnny1982 (Oct 15, 2010)

You're over-complicating the issue of overclocking for other users out there. When I put together my current rig, I started overclocking within a few days of purchase, definitely less than 24hrs. The only problem I had was an inferior cooler that could not handle the temp of my new CPU. Cooler at the time was a Zalman CNPS7000c Al-Cu cooler and an I3-550 CPU. Bought the Cooler Master Hyper 212+ and bob's your uncle, overclocked it from a max of 3,5ghz (Zalman cooler) to 4,10ghz (stock is 3,20ghz). I had an E2160 before that, but that CPU I had for a few years before I could overclock it, as I didn't do enough research and ended up with a motherboard that could not overclock. After purchasing a Asus P5QL-Pro mobo the E2160 could easily be overclocked to 2,70ghz (50% increase) and upto 3,00ghz in winter with the Zalman cooler. 

The main thing you have to keep tabs on are the temps, set the Ram frequency independently from the FSB, otherwise it will automatically ramp-up with the FSB causing BSOD's and restarts and also to set your PCI-E frequency to default at 100mhz. Sometimes it might also be necessary to increase the voltage on the CPU in order for the PC to boot, but extra volts means extra heat, so you have to find the sweet spot.


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## Tyree (May 10, 2009)

There is no definitive to OC'ing. If you feel the need to OC.......... build the PC, install all the software, run Prime 95 per instructions. If it's stable, OC.


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## SwanSword (Aug 18, 2011)

I just got done burning in two CPUs, 3.8 GHz Xeons. I use Arctic Silver, and it is one of the thermal interface pastes that requires high temps for several days in order to cure. I also must mention the importance of using carburetor cleaner (also branded as "Goof Off" latex paint remover) to clean the cpu and heat sink contact areas. 

This preparation leaves zero residue. Even 90% isopropyl alcohol leaves residue, because there's water in it.

As a matter of course, I lap the heat sink using 220, 400, and 600 grit wet/dry sandpaper (the black stuff) wet and laid on a piece of plate glass. I then polish the contact surface with extra fine steel wool. This procedure greatly reduces CPU temps. 

When I first powered up using the new processors, CPU temps were running ~60-65 with all fans full blast, mprime (Prime95 Linux version) on max. After ~72 Hrs. temps had dropped to ~50-55 with fans at lower speed. 

I'm using old Intel processors, i.e. Pentium 4 style, that have slightly raised corners, so I also lap the processors to get rid of the gap.


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