The goal of this book is to condense the knowledge of Over-clocking into an easy to use reference book for anyone who is looking to squeeze a few more frames from their favorite game or that aspiring extreme over-clocker!
Ok, so what exactly is Over-clocking?Overclocking is the process of running a computer chip at a higher clock rate (speed) than it was designed for, gaining an increase in the performance of the computer.
Why Over-clock?most users over-clock rather than purchase new hardware components to keep pace with new software requirements, For example over-clock low-end computer components to higher clock rates equal to or greater than the high-end more expensive components recommended by the game manufacturer.
What can be over-clocked?People who overclock their components mainly focus their efforts on processors (CPU), video cards (GPU), motherboard chipsets, and random-access memory (RAM). It is done through manipulating the CPU multiplier and the motherboard's front side bus (FSB) clock rate until a maximum stable operating frequency is reached, although with the introduction of Intel's new X58, and P55 chipsets and the Core i3,i5,i7 processors, the front side bus (FSB) has been replaced with the Baseclock (BCLK)
and QPI (Quick Path Interconnect);
The Concept of Over-clockingWhile the idea of over-clocking is simple, variation in the electrical and physical characteristics of computing systems complicates the process. CPU multipliers, bus dividers, voltages, thermal loads, cooling techniques and several other factors such as individual semiconductor clock and thermal tolerances can affect it. Every component has its unique limits with higher clocks and voltage. Two identical CPUs may clock completely differently, one being stable with higher clocks at a similar temperature as the other. The bus and memory stability and tolerances also affect how stable an over-clock can be.
Mainstream OverclockingBoard TerminologyPCB:Printed Circuit Board, this multi layer sheet contains layers of circuits "wires" that interconnect all of the components, chips and connectors soldered to the surface of the board.
Power Phase:Phase is commonly referenced to as a CPU voltage regulator module. A voltage regulator creates an output voltage requested by the CPU (Usually in the range of 1-2 volts) by converting the +12V power from the system power supply.
These VRM's contain a number of buck converters, each generating the same voltage and a split of the total output current. Each converter usually consists of 2 or 3 switching MOSFET transistors, one coil and at least one capacitor, plus the driver section which can be a separate SMD or included in the main PWM controller. The buck converters do not work simultaneously but alternate with an equal delay between each others switching, this is why the converter is also called "a phase".
There are many advantages for using multiple power phases, the most important being a reduction in required output capacitor size. Each converter "Phase" takes it's turn switching, making the output ripple frequency much higher due to phase interpolation. For example, if we have a converter that works at 500Khz, for a single-phase we would have 500Khz ripple, but for a 4-phase system the ripple would be at 2000khz, this would allow capacitors of 1/4 the size to be used to filter the power. Another advantage of the phase interpolation process is a much faster voltage load response. One advantage is the current distribution, power is drawn from multiple sources lowering current draw on each phase and distributing the heat generated over a larger area. One drawback to multiple phase designs is the increased generation of EMI caused by the very high-frequency ripple, better capacitors such as Japanese solid capacitors are required for output filters. DPWM "Digital Pulse Width Modulation" regulator modules are able to switch at very high frequencies generating very little heat by using extremely efficient ceramic capacitors.
NVIDIA nForce 200 MCP "nF200":The nForce 200 chip was created as a means of providing SLI functionality to Intel chipsets needed to ensure 4-Way SLI would have full 16x PCI express graphics lanes available to each graphics card.
SATA:
Serial ATA (
SATA or
Serial Advanced Technology Attachment) is a
computer bus interface for connecting
host bus adapters to
mass storage devices such as
hard disk drives and
optical drives. Serial ATA was designed to replace the older
ATA (AT Attachment) standard (also known as
EIDE), offering several advantages over the older
parallel ATA (PATA) interface
BIOS TerminologyBCLK
measured in MHz
Base Clock Increasing your base clock increases your CPU core clocks, memory speed, QPI frequency, and North Bridge Frequency
-Similar to the older FSB “Front Side Bus”
BCLK x CPU ratio = CPU frequency
Adjust the BCLK frequency to overclock the CPU speed!
-Multiplier is a ratio that determines the clock speed for the CPU based on the multiplication of the BCLK. For example, your CPU multiplier determines what your CPU core clock speed is using this formula: Base clock * multiplier
There are also multipliers for Memory frequency, QPI speed, and North Bridge (UCLK) frequency.
PCIE
measured in MHz
Periferal Connect Interface Express
-Video Graphics communication link
when overclocking, increasing the PCI-E clock can help with stability when above 200MHz BCLK
CPU Voltage
AKA -VCore this is your processor core voltage. Increasing this will supply your CPU cores the power they need to operate at higher frequencies.
Central Processing Unit
-Processor core voltage
DO NOT EXCEED 1.55v
IMC Voltage
"VTT" or "QPI" Increasing this will supply the power needed for the IMC (North Bridge) to operate at higher frequencies.
- L3 shared cache
- memory controller
- processor I/O power rail
Since memory controller frequency is dependent on BCLK, the higher the BCLK, the higher the IMC voltage required. DO NOT Exceed 1.45v
DRAM Voltage
DDR3 Random Access Memory
-Memory Voltage
Since DRAM speed is linked to the BCLK the higher the BCLK the higher the DRAM Voltage is needed
CPU PLL Voltage
PLL: Phase Locked Loop voltage
- Processor/IMC(Integrated Memory Controller)/other internal clock cycles
- Clock multiplying of processor is provided by an internal Phase Locked Loop
Does not have a significant effect on CPU Speed, -DO NOT Exceed 1.90v
PCH Voltage
Platform Controller Hub
- main I/O interface for CPU
- display connectivity
- Integrated Audio
- power management features
- Storage features
The higher the CPU frequency, the harder the I/O (input and output) has to work so there is higher power consumption and more heat is generated, raising the CPU temperature. The PCH voltage needs to be increased in order to stabilize I/O signaling. DO NOT EXCEED 1.25v
ICH:
I/O Controler Hub or South Bridge chip
controls:
PCIe ports: usually 1x 2x 4x
PCI Bus
SATA ports, eSATA ports
Intel Audio
integrated LAN Port
USB Ports
I/O:
In
computing,
input/output, or
I/O, refers to the communication between an
information processing system (such as a
computer), and the outside world, possibly a human, or another information processing system.
Extreme OverclockingCooling Terminology:Cold Bug: CB or Freeze Lock
The below zero operating temperature at which the CPU locks up and becomes non responsive
Cold Boot Bug: or CBB
The minimum temperature the CPU can bee at to successfully turn on or POST from an off state.
POT:
A type of heatsink used for Liquid Helium, Liquid Nitrogen, and Dry Ice cooling
Phase Cooling:
The use of a Mechanical refrigeration system similar to a home freezer or refrigerator to cool a microprocessor below room temperature