Soldato
Think there is a P5K specific OC guide floating around somewhere 
**- Official Asus P5K Thread -**
- Thread starter lay-z-boy
- Start date
Right very simple guide to get you started.
Right thats what you need to do first.
Now the settings:
CPU Ratio Setting: Should already be set at your CPU's maximum multiplyer.
FSB Strap to North Bridge: This depends on your overclock and Ram speed. Intitially you'll probably want to set it to 333mhz. Then maybe increase it to 400mhz (with latest BIOS) if you reach a high clock and are limited by your Ram)
FSB Frequency: This is the overclocking bit. The FSB * CPU Ratio = Clock speed so, for my E2120 i know 3ghz is a common overclock. So i set it to 333mhz becuase its a safe bet it will boot at 2.7ghz.
PCIE Frequency: Set this to 100, some boards 101 adds stability to overclocks but can't say it changes much on P5K afaik.
DRAM Frequency: Change this to suite your ram. Idealy (to start with) under but close to its rated speed, if the speeds listed are too low, decrease FSB Strap to North Bridge. If the listed DRAM speeds are too fast INCREASE FSB Strap to north bridge.
DRAM Command Rate: 2N
DRAM Timing Control: For now, since we are not overclocking the Ram auto should do.
Dram Static Read Control: Disabled seems to increase stability when overclocking.
Transaction Booster: Leave this as auto.
CPU Voltage: This is where you must be carefull. Using coretemp look for your CPU's VID. This is its recommended voltage or "stock volts". Try not to go above this, doing so will increase tempretures etc. If you need to go over it to stabilize an overclock do it in notch at a time. My Vid is 1.325 so im leaving it on that since im only doing a mild overclock.
CPU PLL Voltage: With quad cores increase PLL voltage seems to have a greater affect on overclocks, with duals until you get to superclocks can probably leave it auto.
FSB Termination Voltage: Same as above
DRAM Voltage: Set this to your rams voltage, since for now your not overclocking RAM you don't need to go over.
NB Voltage: Depending on your motherboard you may/may not need to icnrease NB voltage. Anything upto 400FSB and you sould be fine with Auto
Clock over-charing voltage: Again auto should do for now
Load-Line Calibration: If enabled this reduces vdroop. Intel spec says vdroop is a feature, overclockers thinks its a PITA. Enabled for nice stable voltages imo.
CPU and NB GTL Voltage Reference: 0.61x seems to be fine, however im not sure what it does so i've left it on auto.
CPU and PCIE spread spectrum: Disabled, increases stability.
Right thats what you need to do first.
Now the settings:
CPU Ratio Setting: Should already be set at your CPU's maximum multiplyer.
FSB Strap to North Bridge: This depends on your overclock and Ram speed. Intitially you'll probably want to set it to 333mhz. Then maybe increase it to 400mhz (with latest BIOS) if you reach a high clock and are limited by your Ram)
FSB Frequency: This is the overclocking bit. The FSB * CPU Ratio = Clock speed so, for my E2120 i know 3ghz is a common overclock. So i set it to 333mhz becuase its a safe bet it will boot at 2.7ghz.
PCIE Frequency: Set this to 100, some boards 101 adds stability to overclocks but can't say it changes much on P5K afaik.
DRAM Frequency: Change this to suite your ram. Idealy (to start with) under but close to its rated speed, if the speeds listed are too low, decrease FSB Strap to North Bridge. If the listed DRAM speeds are too fast INCREASE FSB Strap to north bridge.
DRAM Command Rate: 2N
DRAM Timing Control: For now, since we are not overclocking the Ram auto should do.
Dram Static Read Control: Disabled seems to increase stability when overclocking.
Transaction Booster: Leave this as auto.
CPU Voltage: This is where you must be carefull. Using coretemp look for your CPU's VID. This is its recommended voltage or "stock volts". Try not to go above this, doing so will increase tempretures etc. If you need to go over it to stabilize an overclock do it in notch at a time. My Vid is 1.325 so im leaving it on that since im only doing a mild overclock.
CPU PLL Voltage: With quad cores increase PLL voltage seems to have a greater affect on overclocks, with duals until you get to superclocks can probably leave it auto.
FSB Termination Voltage: Same as above
DRAM Voltage: Set this to your rams voltage, since for now your not overclocking RAM you don't need to go over.
NB Voltage: Depending on your motherboard you may/may not need to icnrease NB voltage. Anything upto 400FSB and you sould be fine with Auto
Clock over-charing voltage: Again auto should do for now
Load-Line Calibration: If enabled this reduces vdroop. Intel spec says vdroop is a feature, overclockers thinks its a PITA. Enabled for nice stable voltages imo.
CPU and NB GTL Voltage Reference: 0.61x seems to be fine, however im not sure what it does so i've left it on auto.
CPU and PCIE spread spectrum: Disabled, increases stability.
Associate
Tried my first overclock. Changed the settings that I needed to chnage to manual first. I decided to start with 333x9 to get 3.0ghz prime failed after 14 min. I read somewhere that its best to slacken the memory timings first prior to overclocking, so on this advice I set the timings from 5-5-5-15 to 5-5-5-23 and this made it stable. I ran prime for 2 hours and it was stable.
So I then tried 400x8 to give 3.2ghz leaving the timings at 5-5-5-23 and core voltage at 1.272 again it was stable on prime for 2 hours. One thing I did notice is when I increased the sped to 400x8 in the bios the DRAM Frequency automaticaly changed to 1280Mhz in the bios too, so I lowered it down to 1000Mhz is this ok ?
The memory I am using is Crucial Ballistix Tracer PC2-8500C5 1066MHz just wanted to know if I should have altered it back to near its normal speed or left it on 1280mhz which seems high. It is very stable on these settings and load temps never go above 42 running at 3.2Ghz.
So I then tried 400x8 to give 3.2ghz leaving the timings at 5-5-5-23 and core voltage at 1.272 again it was stable on prime for 2 hours. One thing I did notice is when I increased the sped to 400x8 in the bios the DRAM Frequency automaticaly changed to 1280Mhz in the bios too, so I lowered it down to 1000Mhz is this ok ?
The memory I am using is Crucial Ballistix Tracer PC2-8500C5 1066MHz just wanted to know if I should have altered it back to near its normal speed or left it on 1280mhz which seems high. It is very stable on these settings and load temps never go above 42 running at 3.2Ghz.
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Up to you,
Myself and others tend to get a stable CPU overclock first. Then find a good clock for the Ram, then tighten the timings. Then tighten the voltages.
But I think anyone would say sort out your CPU clock before worrying about Ram and stuff, otherwise it gets bloody confusing working out whats making it unstable!
Associate
Thanks allllec, it is stable at the moment on these settings
vcore 1.275 at 3.2ghz, temps very low, ddr2 timings changed to 1000mhz its prime stable too. However when I look in CPU-Z it says DRAM frequency is 500.0mhz but in the bios its 1000mhz any ideas ?
This my first ever attempt at overclocking so go easy
vcore 1.275 at 3.2ghz, temps very low, ddr2 timings changed to 1000mhz its prime stable too. However when I look in CPU-Z it says DRAM frequency is 500.0mhz but in the bios its 1000mhz any ideas ?
This my first ever attempt at overclocking so go easy
Associate
Ah I see, phew thought there was a problem cheers allllec
Associate
Just make sure you ram is running at 2.2v and its memtest stable
My PC5300 Ballistix run 1066mhz at CL4! D9 chips rock!
My PC5300 Ballistix run 1066mhz at CL4! D9 chips rock!
Associate
How do I check if its at 2.2v is that in the bios ?
Edit- found the option to change the dram voltage in the bios. It was set to auto. I have now changed it to 2.20V.
Edit- found the option to change the dram voltage in the bios. It was set to auto. I have now changed it to 2.20V.
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Associate
Hi Alllec thanks for the help so far. Struggled a bit in the bios some of the features you mentioned are not in mine? I have bios v0704. What is the easiest way to update the bios? I did it through windows and it messed it up so this is my second board.
I have overclocked it through the Asus Ai Suite and currently have it at 2.5Ghz but when i try any higher it crashes?????? Any suggetsions?
Sorry as you can tell first time at this.
I have overclocked it through the Asus Ai Suite and currently have it at 2.5Ghz but when i try any higher it crashes?????? Any suggetsions?
Sorry as you can tell first time at this.
Yeah updating BIOS through windows is pretty riskey.
However on the P5K you can download a new BIOS off the asus site, put it on a USB stick. Alt+F2 when your computers booting and flash it through that, safest way.
My bios just looks a bit different becuase it's on the latest bios. The important settings are roughly the same, although you wont have a 400mhz FSB strap.
With your CPU i imagine you could probably get away with going into the bios and settings multiplyer to 9 and putting FSB straight on 333mhz. Giving you just under 3ghz.
However on the P5K you can download a new BIOS off the asus site, put it on a USB stick. Alt+F2 when your computers booting and flash it through that, safest way.
My bios just looks a bit different becuase it's on the latest bios. The important settings are roughly the same, although you wont have a 400mhz FSB strap.
With your CPU i imagine you could probably get away with going into the bios and settings multiplyer to 9 and putting FSB straight on 333mhz. Giving you just under 3ghz.
Associate
Thanks again Alllec will give it a go.
Edit: Just to add a bit more. Tried what you said alllec but no luck. Went in with 333 X 9 as you said comp boots but there is no display on the screen??????
Edit: Just to add a bit more. Tried what you said alllec but no luck. Went in with 333 X 9 as you said comp boots but there is no display on the screen??????
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Soldato
Flash to 1004, works perfect here
Associate
Mr Paul, hes using a different board.
Tainted, its now called load line calibration
-CPU Voltage Reference is now called CPU GTL Voltage Reference
-NB Voltage Reference is now called NB GTL Voltage Reference
-CPU Voltage Damper is now called Load-Line Calibration
hope that helps you
Tainted, its now called load line calibration
-CPU Voltage Reference is now called CPU GTL Voltage Reference
-NB Voltage Reference is now called NB GTL Voltage Reference
-CPU Voltage Damper is now called Load-Line Calibration
hope that helps you
Mr Paul, hes using a different board.
Tainted, its now called load line calibration
-CPU Voltage Reference is now called CPU GTL Voltage Reference
-NB Voltage Reference is now called NB GTL Voltage Reference
-CPU Voltage Damper is now called Load-Line Calibration
hope that helps you
Cheers mate. My Gigabyte DS4-P35 had that. Oh well I cant break the stable 3.8ghz mark. New PSU and motherboard and still stuck at 3.6ghz.
Thanks for those name changes mate.
Associate
Are temps holding you back? depending on the chip you may need in excess of 1.5v to get a stable 3.8GHz.
Fact is your old Gigabyte DS4-P35 was probably a decent board, I doubt it held your quad back.
I keep thinking I need a new PSU every time I run prime, damn rails drop a wee bit at 1.5V but it stays within spec. Hard gaming also has the same effect but the PSU stays cool.
Fact is your old Gigabyte DS4-P35 was probably a decent board, I doubt it held your quad back.
I keep thinking I need a new PSU every time I run prime, damn rails drop a wee bit at 1.5V but it stays within spec. Hard gaming also has the same effect but the PSU stays cool.
Associate
Be carefull flashing to the latest bios mine would not even post with 1004+1006....i had to mix the ram to get it going...and i'm not the only one who have had ram problem....Elixir pc8500 no boot!...Geil pc6400 no boot! ( yes tried all 4 slots) 1 stick of each boot!
Just a little update....now able to run latest bios 1006 with no issues at all with my mem thanks to SPDtool...used it to actually alter the memory's SPD so the mobo see's my Elixir memory now as only 667mhz and posts fine as before it would not!.
LOL - yeah the P35-DS4 was probably an ok board. But I also wondered about PSU so now replacing both I have cured that nagging feeling. Not much improvement at all!
I'm on watercooling and when I try high voltages like 1.6v to see if it will make it it's normally at night with window open on radiator and temps are around 55c.
1.475 volts (BIOS) is currently 9 hours stable at 3.6ghz. I can post at 4ghz but seems a mission to go from 3.6 to even 3.8ghz. Ran my 3D mark benches at 3.8ghz on Gigabyte board.
What board you running?
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Associate
Same as you, takes me 1.5625V (1.536V in windows) to get 4GHz stable and 1.4625v (1.44v in windows) to get 3.8GHz stable.
After trying every setting I found that non actually improved or influenced my clock. I could leave every setting bar vcore on auto and I could still reach the maximum potential out of the chip.
After trying every setting I found that non actually improved or influenced my clock. I could leave every setting bar vcore on auto and I could still reach the maximum potential out of the chip.