*********************Part I - "Basic Overclocking"*********************Note: Each motherboard version, each motherboard manufacturer, each motherboard revision is different. Hence, it is important to get intimate with your hardware. This basic will teach the concept, but how you go about tweaking your hardware will be different from one motherboard to another, even if they are of the same motherboard manufacturer or chipset.
Due to such variation, it is impossible to make a one-size-fit-all-specific overclocking basic, since the option to tweak the settings will be different from one motherboard to another. This basic is a generic step to achieving your overclock.
Introduction:So, you like to overclock your Intel® Pentium® 4, Intel® Pentium® D, Intel® Core™, and Intel® Core™ 2 Duo processor but don't know where to start and kept asking here and there, hither and yonder? Are you tired asking questions? Me too!!! =) So I made this litol artikol.
Pre-requisite:(*) Know your hardware, get familiar with it. Read the manual, etc.
(*) A CPU of course.
(*) A decent DDR1-400 RAM for Socket478 CPU and DDR1-based Chipset.
(*) A decent DDR2-667 RAM for LGA775 CPU and DDR2-based Chipset.
(*) A good overclockable motherboard
(*) A very good PSU, preferably branded ones, with dual 12v rail, and 20a+ rating on the 12v rail (and good 3v an 5v rail as well).
(*) Temperature monitoring software
(*) Software and stress testing utilities
(*) A clean, well lit, properly ventilated working area
(*) Money to burn in case you mess up, drinks, high morale
(*) And this guide
Optional:
(*) Temperature monitoring device
Disclaimer:
Overclocking is dangerous to your rig, voids your warranty, and can harm you emotionally and physically. Do at your own risk.
This also covers Intel chipsets only, 3rd party chipset may or may not behave the same way. Proceed with caution!Elementary Preparation01) Boot your system on stock, run benchmarks preferably for 1hr continous loops, and record idle, average, and peak temperature.
02) Set your heatsink fan controller to manual, and in full/maximum power.
03) Set your Memory a step down lower, i.e. from DDR400 to DDR333 (5:4), from DDR2-533 to DDR2-400, etc.
04) Set your Memory Timing to SPD, or check the markings on the RAM, add +0.5 to 1.0 value to each, and enter it on the BIOS i.e. CL2.5-3-3-6 to CL3-4-4-7, CL4-4-4-12 to CL5-5-5-5, etc.
05) Set your vCore to Auto
06) For AGP based system, set your vAGP/vNorthBridge to 1.7v.
07a) For
DDR1, set your vDimm to 2.75v
07b) For
DDR2, set your vDimm to 1.9v
08) Disable Spread Spectrum.
09a)
For chipsets i875 and earlier, lock your PCI and AGP (set PCI at 33Mhz and AGP at 66Mhz).
09b)
For chipsets i915/i925/i945/i955/i965/i975, lock your PCI (set PCI at 33Mhz), and set your PCI Express Frequency to Auto.
What the above steps does is eliminate any (elementary) possible bottleneck. For example, on DDR1 based system, you are not going to hit memory limitation until around 260-270 FSB. And at that memory speed, your vDimm will be more than enough to provide juice.
Setting vCore on stock ensure you don't kill your CPU drastically (but that doesn't mean you can't kill your CPU).
Setting vAGP to a decent voltage ensure you will not be hampered by motherboard, but it does put your overall system in low to moderate risk.
Intermediate Preparation10) Ensure you monitor the Northbridge heatsink temperature
11) Ensure you monitor the CPU temperature
12) Ensure you monitor the Heatsink temperature
13) Ensure you monitor the Case temperature
14) Optionally, monitor the Hard Disk temperature
Final Preparation15) Bump your FSB to 276 (Conroe, Prescott 2M), 210 (Northwood C, Prescott E), 143 (Northwood B, Prescott A), 110 (Any 400Mhz FSB CPU)
16) Boot, run benchmarks preferably for 1hr continous loops, and record idle, average, and peak temperature.
17) Compare the temperature with your stock settings. If temperature goes up 10c higher than stock, stop and get a better heatsink or review your case ventilation. Otherwise, go to next step.
Start up the conking18) Bump the FSB 5 notches
19) Boot, run benchmarks preferably for 15mins continous loops, and record idle, average, and peak temperature.
20) Compare the temperature with your stock settings.
The general rule (not the absolute) is to:
(*) Keep your CPU as cool as possible, near ambient temperature.
(*) For Idle, maintain half the allowed Thermal Specs of your CPU. So if you have a 69c rated CPU, maintain at least 34c idle.
(*) For Load, maintain 10c higher than idle without hitting the maximum rated Thermal Spec OR
(*) For Load, keep it around 85% less than your CPU's rated temperature. For example, a 69c rated CPU can hit as high as 59c.
(*) Keep your Case temperature to 38c as much as possible.
(*) Keep your Northbridge below 45c as much as possible
21) If your OC is stable, go back to steps 18-20. If not, proceed to the next step.
22) You MAY have hit the wall. Which is it? It's up to you to find out and have fun.
(*) Maybe your CPU needs more voltage?
(*) Maybe your CPU needs to be cooler?
(*) Maybe it's the max your CPU can handle?
(*) Maybe your RAM hate lax timing or tight timings?
(*) Maybe your RAM needs more voltage?
(*) Maybe your RAM needs to be cooler?
(*) Maybe it's the max your RAM can handle?
(*) Maybe your Northbridge needs more voltage?
(*) Maybe your Northbridge needs to be cooler?
(*) Maybe it is the max your Northbridge can handle?
(*) Maybe your PSU needs to replaced?
(*) Maybe you need to look into your SouthBridge?
(*) Maybe you need to tweak more and check the rest of this OC article?Discusss this article or your Intel® Overclock here:
http://www.tipidpc.com/viewtopic.php?tid=13755******************Part II - "Adbentyuring more"******************Note: While this article was written during the era of DDR(1), the idea still applies very much with newer DDR2Disclaimer:I am
not a mathematician, and the formula below maybe in error. I am
poor at mathematics, written/spoken English, and spelling. So have fun poking at the mistakes...
This post is based on my opinion alone, and does not encompass or embody the forum's general mindset or anybody else's.
You have been forewarned. Use (and read) at your own risk.
Note: Specifically geared for Intel® Processors, but the general idea can be used on alternative processors.
Overclocking My DummyScenario 0:"All my friends have the new and baddest PC. I gotta have me one"I. Teh uncool abbreviations used:(*) DDRfrq = DDR (not SDR) frequency. They come in many flavors. Usually, they come in DDR266(PC2100), DDR333(PC2700), DDR400(PC3200) flavors. Please, don't ever say or call DDR400 as PC400.
(*) QPB = Quad Pump Bus architecture for Intel®. This means, you multiply the FSB by 4 to get the QPB value.
(*) PSB = for the lack of a better abbreviation, let's just call it PSB for CPU front side bus. This is the rated FSB of the CPU (or PSB=Processor System Bus).
(*) CPUmul = again, for the lack of a better abbreviation, I used that. It's just the CPU multiplier.
(*) CPUfrq = bah, I can't think of any good abbreviation, but what I mean here is the rated speed of your CPU.
(*) FSB = dang, I'm bad at coining abbreviations. But in any case, this is the motherboard Front Side Bus frequency.
II. Going Back to Basics: (
Thank goodness, it's not going back to school. I hate that slogan or whatever you can call it.)
(*) DDR Basic: You can get the DDRfrq, assuming it's on stock, by simply using the default multiplier of 2 (hence the term double data rate).
DDRfrq = FSB * 2
(*) QPB Basic: This is a constant value used on current generation P4, and it's not changeable. Well, as far as I know of.
QPB = 4 (*Hint: for Intel® NetBurst and Core™ architecture)
(*) Formula: So, what are these. Nothing really special, except, they can be used on your OCing computation. This formula shows how you can get specific values. For example, to get the equivalent motherboard (or Bios setting) FSB, you divide the CPU's rated PSB with QPB (or 4). The CPU multiplier is easy to get as well, just get the CPU's frequency, and divide it by the rated motherboard FSB and there you have it. To get the rated speed of the CPU is quite straight forward: multiplier times the fsb!!!
FSB = PSB / QPB
CPUmul = CPUfrq / FSB
CPUfrq = FSB * CPUmul
So, why don't we move on to some actual mind boggling (*I wish*) computation.
III. The elementary computation of the whole wide world:Scenario 1:"Oh, so I have this nice brand spanking new Intel® Pentium® 4 2.4C 800Mhz 512kb L2 cache Northwood. I also bought a kinky little dual channel kit ram, in the incarnation of generic DDR400. My killer ECS PF3 800FSB Photon Edition can smoke them all. Oh, this is so sweet, I am salivating already. I mean, what could be faster than my rig? Oh well, I guess only dorks and newbies will call this rig slow. Besides, my HIS MX440 is so sexy, girls at school will be begging to go out with me. I RULE!!!"Given:CPUfrq = 2400
FSB = 200 (800FSB / 4)
Unknown:CPUmul = ?
Finding the multiplier is simple
CPUmul = 12 (2400 / 200)
IV. Moving on to the next step, killing the pulp, one big stroke at a timeScenario 2:"Dang, my classmates smash my PC when it comes to benchmarks. Is there any way I can bring this to 3.0Ghz? I've read somewhere it's possible, but who in the world could have such powers? Am I not that powerful? Am I not God? Am I not teh 133t good looking guy next door? The world must be imploding, it must be the end of the Earth as we know it."Given:Stock CPUfrq = 2400
Target CPUfrq = 3000
Stock FSB = 200 (800FSB / 4)
CPUmul = 12
Unknown:Target FSB = ?
Using the formula above,
CPUfrq = FSB * CPUmul
Substituting the values:
3000 = FSB * 12
Interpolating (is this the correct term?)
FSB = 3000 / 12
FSB = 250
Validating
3000 = 250 * 12
V. Death of an innocence, you just made my dayScenario 3:"The Bios boot up screen shows 250x12=3000 Mhz I AM GOD!!!!" *beep* *beep* *beep*
"What the.dang, won't boot to Windows. Maybe I need to shout louder then press reset, 1..2..3..I AM G.."*beep* *beep* *beep*."
Inspecting the original scenario,
DM, yes, that's the name of the bratty little 14yr old kid, did finally reach his goal of 3Ghz. But that wasn't stable at all. We know what the potential problems are: Northbridge voltage, CPU voltage, AGP voltage, RAM voltage, or even RAM frequency and timing. Since we don't want to delve ourselves into the dark arts of voltage modding, we'll just suffice ourselves to adjusting not-so-dangerous settings. So, he's got a DDR400, OCed to DDR500. Realistic? Maybe. Possible? Maybe. But this is really very obvious now. The memory is just isn't designed for that frequency (btw, the same can be said for the Mobo and CPU). So, what do we do? We isolate which is which.
The divisor:If you are planning an asynch OC, you might want to use the so called divider. Revisiting our DDRfrq formula:
(*) DDRfrq = FSB * 2
It can be re-written as:
(*) DDRfrq = (FSB (DDRmul/DDRdiv)) * 2
In a 1:1 settings, it will yield us this:
(*) DDRfrq = (FSB (1/1)) * 2
Which is actually equal to this:
(*) DDRfrq = FSB * 2
So what in the heck do we need those
DDRdiv and
DDRmul for? Well, to play with a certain OC settings, pushing one area without putting as much pressure on the other. Ding ding ding.so, how about we keep our memory low and put pressure on the CPU instead? Getting the values from Scenario 2:
Given:Target CPUfrq = 3000
Target PSB = 250
Target FSB = 200
CPUmul = 12
Using the formula for DDRfrq and a 5:4 divider (remember that DDRdiv/DDRmul thingy?)
Given:Target CPUfrq = 3000
Target PSB = 250
Target FSB = 200
CPUmul = 12
DDRdiv = 5
DDRmul = 4
Unknown:Target DDRfrq = ?
Therefore:
DDRfrq = (FSB (DDRmul/DDRdiv)) * 2
DDRfrq = (FSB (4/5)) * 2
DDRfrq = (250 (0.8)) * 2
DDRfrq = 200 * 2
DDRfrq = 400
VI. Killing the goat, dead on its tracks!!!Scenario 4:"Oh goody, system boots up, goes to Windows, and Prime95 stable. I must be better than God!!! I am more than a God!!! Hahaha, I RULE!!!!!!!! Worship me!!!! **toot**" SiSoft Sandra finished RAM Bandwidth Benchmark.
"FREAKSHOW!!! Not much improvement on the memory arena!!! This is blasphemy. This is a CURSE. I will vanish thee from the face of the Earth for all eternity!!! Begone, demon of creepiness.out of my sight!!!"Poor bloke, have to spend money to upgrade his RAM to DDR500. Now, go solve his needed RAM frequency on your own ;)It's pretty obvious. And if it is not obvious, most, if not all, of the basics are covered anyway to help solve the needed improvement area.
VII. Seven, yes, this is section 7.We can derive both frequency of the front side bus, as well as the needed memory, and getting the CPU speed target using basic math skills. CPU and Memory ratio can be set to put certain aspect of strain from one or the other or both.
When using a divider, you are "slowing/speeding" one aspect to "catch up" with the other part of the system. For example, a 5:4 ratio will slow down the RAM, while the 4:5 will speed it up, and the 1:1 just means that both the CPU and RAM runs at the same frequency.
Discusss this article or your Pentium Overclock here:
http://www.tipidpc.com/viewtopic.php?tid=13755
