[LittleJay]

thanks for the guide it was a great help
If anyones interested ive worked out an equation to find out what your graphics clock should be set to to keep it from overclocking with your base clock.

a=Overclocked Base Clock
b=Default Base Clock
c=Default Graphics Clock
x=New Graphics Clock

x=c/(a/b)

for example say you have an i3 with its gfx clock at 733, your default bClock is 133 and its overclocked to 210

a/b = 210/133 = 1.5789...
c/1.5789... = 733/1.5789 = 464

So you would set you gfxClock to 464

Hope thats useful for someone

[Brolloks]

Originally Posted by DreadCthulhu

The guide mentions that sometimes the machine might not post at all and then you'll pretty much have to reset the bios. A couple of related question:

- What is usually the cause for the inability of the computer to post? Low VCore or VTT? It'd be good to know in case you made a tweak and all of a sudden the box won't boot and you have no idea what can be improved about the previous set of settings.

Because of the number of variables it is recommended to start OCing slowly as the guide decribes, increments rather than large changes which normally results in no post and failute to boot. I always save my last successfull OC so I can restore it even if I have to reset the CMOS, it acts as your baseline or fallback in case something goes wrong.

If you set your QPI, uncore or RAM speeds too high it almost always result in a no-post an your system will not start up, so be carefull when you OC those, again, small incremental OC steps work.

If you are end up in Windows and get BSOD under stress testing it is either one of two most of the times, low Vtt or low V-core. Once again I have found that Vtt is 3 out of 5 times the culprit. If you make it pass booting but get BSOD as you enter Windows then it is most probably lack of v-core

- What do you do in case there's no CMOS reset button? Pull the battery out? All boards have CMOS reset options, either in the form of a push button or a jumper, consult your board manual to see what applies to your particular motherboard, If all else fals pulling the battery will certainly reset the CMOS and set bios to default settings.

- Sometimes a certain set of settings works fine and resets fine, and is perfectly stable throughout tests, but then it might not post the next time you turn on the machine. Why? Albeit not very often I have come across what you are describing, what I have found is more often the board is not fully compatible with the RAM you using or the bios is unstable, in such a case try updating the bios or as a last resort RMA the board, as I said it does not happen much but it has a change to stock out its head now and then.

Very good questions See above

[DreadCthulhu]

Originally Posted by Brolloks

Very good questions See above

Thanks for the responses. About the last point, I'm getting this strange "won't post despite good stability" issue right now on my box. It was working fine before I started OCing, but once I started then it would occasionally either:

- start to boot, but then audibly restart before the post screen. Sometimes 1-3 times, then eventually it would post and work fine afterwards.

- not post at all, which is what I ran into.

The reason why I don't think the RAM is the issue is because this no-post issue was never there when the system was at stock values, so I'm trying to determine what exactly was fubarred.

[Brolloks]

What CPU , RAM and board are you using? When I say RAM is not compatible it is really at OC state, at stock pretty much everything should run fine 99% of the time.

[DreadCthulhu]

Originally Posted by Brolloks

What CPU , RAM and board are you using? When I say RAM is not compatible it is really at OC state, at stock pretty much everything should run fine 99% of the time.

I'm using:

2 x G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)

Intel Core i5-750 Lynnfield 2.66GHz

GIGABYTE GA-P55M-UD2 LGA 1156 Intel P55 Micro ATX Intel Motherboard

What's ironic is that I picked those sticks specifically because they were supposedly compatible with that board.

[Brolloks]

What was your OC when you started getting issues and what voltages were you applying?
Not that the UD2 is a bad board but it has limitations to OC.

[DreadCthulhu]

Originally Posted by Brolloks

What was your OC when you started getting issues and what voltages were you applying?
Not that the UD2 is a bad board but it has limitations to OC.

Actually I lied. I just reset the settings through the jumper and it still takes 2-3 attempts to boot.. That's weird. Shouldn't be the lack of power either, it's a 750W PSU.

[wickedout]

Very nicely written. Great read and good understanding for many of us. Thanks again.

[Brolloks]

Originally Posted by DreadCthulhu

Actually I lied. I just reset the settings through the jumper and it still takes 2-3 attempts to boot.. That's weird. Shouldn't be the lack of power either, it's a 750W PSU.

I would venture to say your board is FUBAR, RMA it or return for exchange.

[psionic98]

1 - on initial post---bad factory setting.. resetting cmos helps usually or its a dead board
2 - yes pull battery for 30seconds and replace
3 - not sure, can post this in another thread on its own

[jamsde]

Wow what a very well written and informative guide, thank you so much for posting it! I just finished building an i920 system for gaming and will be using your guide to tune the overclocking. Thanks again! I'll post my results


Jon

[MIAHALLEN]

Originally Posted by wickedout

Very nicely written. Great read and good understanding for many of us. Thanks again.

Originally Posted by jamsde

Wow what a very well written and informative guide, thank you so much for posting it! I just finished building an i920 system for gaming and will be using your guide to tune the overclocking. Thanks again! I'll post my results


Jon

Thanks for the positive comments guys....I'm glad we could help

Please post your specific system related questions in a new thread. This thread should be for comments or questions about the guide only, thanks

[dominick32]

MIAH, just took a gander at this on the homepage. Excellent review bro!

Dom

[MIAHALLEN]

Thanks Dom

[urasofty]

Hello ive been following this guide and i just have a question regarding vcore.
Im using p55m-ud2 mobo + i3 btw. When im trying to tweak my vcore how do i increase it in increments of 0.025V? in the bios the only available options are 0.5V+, 0.550V+, etc. am i missing something here?

[dominick32]

Originally Posted by urasofty

Hello ive been following this guide and i just have a question regarding vcore.
Im using p55m-ud2 mobo + i3 btw. When im trying to tweak my vcore how do i increase it in increments of 0.025V? in the bios the only available options are 0.5V+, 0.550V+, etc. am i missing something here?

Dont worry my friend. This is just a general guideline more along the lines of "raise vcore how you feel comfortable doing it". If your motherboard only allows certain intervals than use the smallest interval offered.

However, I think you may be wrong with your numbers. A bump of .50 is not possibly the smallest option on a mobo seeing that normal VID is between .98 and 1.3625 on Intel processors, so bumping up vcore .5 would essentially burn out your chip with too much heat and volts in one simple bump. lol So, I am assuming you mean .055v? Please make this correction before we proceed.

Dom

[urasofty]

Originally Posted by dominick32

Dont worry my friend. This is just a general guideline more along the lines of "raise vcore how you feel comfortable doing it". If your motherboard only allows certain intervals than use the smallest interval offered.

However, I think you may be wrong with your numbers. A bump of .50 is not possibly the smallest option on a mobo seeing that normal VID is between .98 and 1.3625 on Intel processors, so bumping up vcore .5 would essentially burn out your chip with too much heat and volts in one simple bump. lol So, I am assuming you mean .055v? Please make this correction before we proceed.

Dom

Sorry, I'm an idiot >_<. While looking at vcore in bios i assumed that every bump is added to the listedl cpu voltage (i.e. 1.103V + 0.50). The minimum number given was 0.50 which obviously means changing the voltage to 0.50 not actually bumping it by 0.50. Stupid mistake ! =[

[baditude_df]

What a fantastic Guide! It's really well laid out and an easy read.
Thank you MIAH and all who contributed!

But what's missing from this picture?

Core i7 (Bloomfield – i7 920, 940, 960, 965/975)

:looks down at poor lonely 950:

[MIAHALLEN]

Thanks Pat...

I left out the i5 950 just for you

[urasofty]

After a couple weeks of using stock cpu speed i decided to try my hand at ocing but have run into some problems. Here is the build - core i3, p55m-ud2, arctic cooler f7 rev 2, 4gb kingston 1333 ddr3- 1.50V stock
Right now my oc is sitting at
3.65 ghz
multiplier x22
bclock 166
vcore on cpu-z @ max load 1.072V
@ bios 1.09v
vtt - 1.20V or 1.10v (stock
ram volts - 1.50V (should this ever be increased)

I've pretty much followed your guide (ram timings, lowest multiplier,etc). I've found leaving the vtt stock while increasing vcore slightly to be just as successful as increasing the vtt and vcore.

Anyways in an attempt to oc a little higher I've experimented by slowly increasing vcore, and bclock to 169,170,175 and it would boot then continue to restart eventually loading default settings if i do not go into the bios. The highest vcore i had was 1.25v @ 172. I'm not sure what the problem is, what are some numbers i should be testing out?
i have not yet increased the ram voltage because i am not even sure if this should even be increased in the first place.