Help me OC my E8400

[D-Rock]

Hey friends. I recently upgraded my watercooling to accommodate the NB and MB VRs. I had my E8400 running 3.8ghz but the NB seemed way too hot and I stopped there. Now the OC journey continues. I want to reach the highest possible overclock for 24/7. I want to push this setup until either temps or voltages are unacceptable for 24/7 use.

Specs are as follows
E8400 E0
Gigabyte GA-EP45-UD3R (pretty much the same as ud3p)
Corsair Dominator 2x2gb 1066 5-6-6-18 (2.1v)
MSI GTX275 Twinfrozr OC edition
2x WD Caviar 160gb sata in RAID 0 on PCIe 1x Raid card
OCZ Gamextreme 700w psu

Cooling is as follows:
Fittings and tubing are 3/8"
Rad: HWlabs BlackIce Alpha Micro II (2x 80mm fan)
Fans: 2x Silverstone RL-FM81 (72.91CFM each)
CPU block: Original Swiftech Apogee
NB block: Swiftech MCW30
VR blocks: Koolance MVR40
Pump: Switech/Laing MCP350 with pressure bypass
Case Fans: 1 intake and 1 exhaust 120mm Fans

Temps so far have not been a problem. With the fans on lowest speeds idle is around 34c load is around 50c.

I am not too familiar with some of these voltages and have been researching them for 2 days now only to come up with alot of contradictory information. I will post my bios settings and we can go from there. All my current settings are below in the quote box. Thanks for any and all help.





Quote:
<table width="100%" border="0" cellpadding="6" cellspacing="0"><tbody><tr><td class="alt2" style="border: 1px inset ;"> MB Intelligent Tweaker(M.I.T.)
Robust Graphics Booster ...............: Auto
CPU Clock Ratio ..........................: 9x
Fine CPU Clock Ratio.....................:.0
CPU Frequency ...........................: 4.14ghz


Clock Chip Control
Standard Clock Control
CPUVirtualization Technology................: [Enabled] </td></tr></tbody></table>

[Chike]

Re: Help me OC my E8400

Which voltages you are intersted of?
Some of them are derived from others and should be set accordingly.
e.g. MCH/DRAM Reference, DRAM Termination, and Channel References, depend on DRAM Voltage, and the default 0.9v corresponds to the default 1.8v DRAM Voltage, better leave them on auto if you don't need to tweak them.
Same with CPU/MCH References, both depand on CPU Termination.
If you do want to set them manually, set them to default voltage with the voltage they depend of at default, then change the voltage they depend on to it's desired value.

Out of curiousity, why set PLL below it's default?

[D-Rock]

Re: Help me OC my E8400

I set the PLL low because I have been reading numerous things across the internet about this voltage as well as the CPU termination voltage and those seemed to be deemed more deadly to the CPU then vcore itself.

I seemed to have figured out some sort of understanding of these voltages but I know I am just scraping the iceberg coming from an MSI 650i board where half of this stuff didnt exist.

Im all too familiar with vcore, I need no help there.

CPU Termination from what I can gather is also referred to as VTT and FSB Termination voltage on some boards. From what I somewhat half@$$ understand this helps with FSB noise reduction at high FSB speeds but high is a relative term. I have also heard that setting this too high can cause instability just like setting it too low. What I would like to know about this voltage is when to use it, what range is acceptable for 24/7 use, and how to know what the right voltage is for different core clock and fsb speeds.

CPU PLL I understand to be the Phase Locked Loop which I know is the clock signal generator. I can wrap my brain around that. What I don't understand is why this is so harmful to a CPU. I would like to know when to use this voltage, at what ranges its acceptable for 24/7 use, and how to know what the right voltage is for different core clock and fsb speeds.

CPU Reference is a mystery to me I have heard that it is also called GTL ref on other boards but IDK what that is. All I know is that its best set somewhere around 64% of the VTT

MCH Core is the NB core voltage, I know what that is and how to use it, no problems there.

MCH Reference, once again IDK what it is or how to use it. Please teach me. I have been doing all my homework but I need more help.

MCH/DRAM Ref, teach me, Havent a clue.

ICH I/O, no problems there. I understand this and when to use it, (which will probably be never for me)

ICH Core, no problems there. I understand this and when to use it, (which will probably be never for me)

DRAM Voltage, no problems here.

DRAM Term, I suppose this does the same thing as VTT for the NB to DRAM. IDK when or how to use it though

ChanA and ChanB ref, dont have a clue.

[BoombasticSloth]

Re: Help me OC my E8400

It might be a good idea to bump your pll up from 1.35v to default 1.50v. It is not going to do you any harm.

It might also be a good idea to bump your MCH/DRAM ref, DRAM termination, channel A & B ref to 50% of your DRAM voltage, ie. 1.05v.

You can leave your cpu and mch ref at 0.76v. You might want to bump up your vtt from 1.20v a step or two. When this is done, your cpu and mch ref will scale up accordingly. You could also reduce your mch and cpu ref 1 or 2 notches down when vtt is at 1.20v, and then bump the vtt up a step or two. The mch and cpu ref will scale up accordingly.

You didn't mentioned what your drive strength is set at. 1066 will be fine.

You also didn't mentioned what your static tRead is set at.

All the best.

[kick]

Re: Help me OC my E8400

How did you determine the nb was way too hot.The finger test?

There isnt really enough activity here on watercooled setups,but check out this article,even tho its more benchmarking than 24/7.
ud3 is also similar to ud3r.
Gigabyte P45 UD3 review - AwardFabrik - Forum

[Chike]

Re: Help me OC my E8400

About Vtt and GTL Reference in Global and how to set them in http://forums.tweaktown.com/f69/how-...asytune-29746/

[D-Rock]

Re: Help me OC my E8400

Thanks friends, i have spent the past few days reading as much as i can in those links you provided me with. Now, I did this,

It might be a good idea to bump your pll up from 1.35v to default 1.50v. It is not going to do you any harm.

It might also be a good idea to bump your MCH/DRAM ref, DRAM termination, channel A & B ref to 50% of your DRAM voltage, ie. 1.05v.

but i didnt understand this

You can leave your <nobr style="font-weight: normal; font-size: 100%; color: rgb(0, 0, 255);" id="itxt_nobr_7_0">cpu</nobr> and mch ref at 0.76v. You might want to bump up your vtt from 1.20v a step or two. When this is done, your cpu and mch ref will scale up accordingly. You could also reduce your mch and cpu ref 1 or 2 notches down when vtt is at 1.20v, and then bump the vtt up a step or two. The mch and cpu ref will scale up accordingly.

Driving strength is at 1066 now since you recommended it and my static tRead is at 11.

I have my setup at 455fsb. It doesnt crash or anything but prime doesnt last too terribly long. I even left the CPU voltage and chipset voltages raised and lowered the multi down to 6 to underclock the CPU and prime got worse, from 2hrs to 13min. What should I do now? I want to go higher but it seems senseless to try to push higher when my current fsb is unstable.

[Chike]

Re: Help me OC my E8400

Where the settings in post #1 stable?
Please post the settings in question.

[D-Rock]

Re: Help me OC my E8400

The settings were not stable as I found out. It failed after 13hrs of prime. I assumed it was stable after a prime run of only 10 hrs but after running for 13 it failed. I lowered FSB a little to 455 to see if it would regain stability and it won't. I lowered the multi of the CPU to test only the FSB and it still remains unstable. This time I included FULL system and BIOS specs.


CPU = E8400 E0 VID: 1.25v
Motherboard = GA-EP45-UD3R Rev: 1.1
BIOS Version = F11
Ram = Corsair Dominator DDR2-1066

[B]MB Intelligent Tweaker(M.I.T.)[/B]
Robust Graphics Booster .................: Auto
CPU Clock Ratio .........................: 6x
Fine CPU Clock Ratio.....................: .0
CPU Frequency ...........................: 2730mhz

[B]
Clock Chip Control[/B]
Standard Clock Control
CPU Host Clock Control...................: Enabled
CPU Host Frequency (Mhz) ................: 455Mhz
PCI Express Frequency (Mhz) .............: 100Mhz
C.I.A.2 .................................: Disabled

[B]Advanced Clock Control [Press Enter][/B]
CPU Clock Drive..........................: 800mv
PCI Express Clock Drive..................: 900mv
CPU Clock Skew (ps)......................: 0ps
MCH Clock Skew (ps)......................: 0ps

[B]
DRAM Performance Control[/B]
Performance Enhance......................: Standard
Extreme Memory Profile (X.M.P.)..........: Disabled
(G)MCH Frequency Latch...................: 400Mhz
System Memory Multiplier ................: 2.00D
Memory Frequency (Mhz) ..................: 910Mhz
DRAM Timing Selectable ..................: [Manual]

[B]Standard Timing Control[/B]
CAS Latency Time.........................: 5
tRCD ....................................: 6
tRP......................................: 6
tRAS.....................................: 18

[B]
Advanced Timing Control[/B]
tRRD.....................................: Auto
tWTR.....................................: Auto
tWR......................................: Auto
tRFC.....................................: Auto
tRTP.....................................: Auto
Command Rate (CMD) ......................: 2

[B]Driving Strength Profiles[/B]
Driving Strength ........................: 1066

[B]Channel A[/B]
Static tRead Value.......................: 11
tRD Phase0 Adjustment....................: Auto
tRD Phase1 Adjustment....................: Auto
tRD Phase2 Adjustment ...................: Auto
tRD Phase3 Adjustment....................: Auto
Trd2rd(Different Rank)...................: Auto
Twr2wr(Different Rank)...................: Auto
Twr2rd(Different Rank)...................: Auto
Trd2wr(Same/Diff Rank)...................: Auto
Dimm1 Clock Skew Control.................: Auto
Dimm2 Clock Skew Control.................: Auto
[B]
Channel B[/B]
Static tRead Value.......................: 11
 tRD Phase0 Adjustment...................: Auto
tRD Phase1 Adjustment....................: Auto
 tRD Phase2 Adjustment ..................: Auto
 tRD Phase3 Adjustment...................: Auto
Trd2rd(Different Rank)...................: Auto
Twr2wr(Different Rank)...................: Auto
Twr2rd(Different Rank)...................: Auto
Trd2wr(Same/Diff Rank)...................: Auto
Dimm1 Clock Skew Control.................: Auto
Dimm2 Clock Skew Control.................: Auto
[B]
Motherboard Voltage Control[/B]
CPU
CPU Vcore................................: 1.27500v
CPU Termination..........................: 1.2v
CPU PLL..................................: 1.5v
CPU Reference............................: 0.760v

[B]MCH/ICH[/B]
MCH Core.................................: 1.2v
MCH Reference............................: 0.760v
MCH/DRAM Refence.........................: 1.050v
ICH I/O..................................: 1.5v
ICH Core.................................: 1.1v

[B]DRAM[/B]
DRAM Voltage.............................: 2.1v
DRAM Termination.........................: 1.050v
Channel A Reference......................: 1.050v
Channel B Reference......................: 1.050v

[B]Advanced Settings[/B]
Limit CPUID Max. to 3....................: Disabled
No-Execute Memory Protect................: Enabled
CPU Enhanced Halt (C1E)..................: Disabled
C2/C2E State Support.....................: Disabled
x C4/C4E State Support...................: Disabled
CPU Thermal Monitor 2(TM2) ..............: Enabled
CPU EIST Function........................: Disabled
Virtualization Technology................: Enabled

[BoombasticSloth]

Re: Help me OC my E8400

Mch and cpu ref's can be a bit confusing.

Let's just work with your your lowered multi's at 6x and your fsb at 455.

When I say drop your mch and cpu ref one notches when vtt=1.20v, and then move the vtt up a notch the following will happen.

[B]MB Intelligent Tweaker(M.I.T.)[/B]
Robust Graphics Booster .................: Auto
CPU Clock Ratio .........................: 6x
Fine CPU Clock Ratio.....................: .0
CPU Frequency ...........................: 2730mhz

[B]
Clock Chip Control[/B]
Standard Clock Control
CPU Host Clock Control...................: Enabled
CPU Host Frequency (Mhz) ................: 455Mhz
PCI Express Frequency (Mhz) .............: 100Mhz
C.I.A.2 .................................: Disabled

[B]Advanced Clock Control [Press Enter][/B]
CPU Clock Drive..........................: 800mv
PCI Express Clock Drive..................: 900mv
CPU Clock Skew (ps)......................: 0ps
MCH Clock Skew (ps)......................: 0ps

[B]
DRAM Performance Control[/B]
Performance Enhance......................: Standard
Extreme Memory Profile (X.M.P.)..........: Disabled
(G)MCH Frequency Latch...................: 400Mhz
System Memory Multiplier ................: 2.00D
Memory Frequency (Mhz) ..................: 910Mhz
DRAM Timing Selectable ..................: [Manual]

[B]Standard Timing Control[/B]
CAS Latency Time.........................: 5
tRCD ....................................: 6
tRP......................................: 6
tRAS.....................................: 18

[B]
Advanced Timing Control[/B]
tRRD.....................................: Auto
tWTR.....................................: Auto
tWR......................................: Auto
tRFC.....................................: Auto
tRTP.....................................: Auto
Command Rate (CMD) ......................: 2

[B]Driving Strength Profiles[/B]
Driving Strength ........................: 1066

[B]Channel A[/B]
Static tRead Value.......................: 11
tRD Phase0 Adjustment....................: Auto
tRD Phase1 Adjustment....................: Auto
tRD Phase2 Adjustment ...................: Auto
tRD Phase3 Adjustment....................: Auto
Trd2rd(Different Rank)...................: Auto
Twr2wr(Different Rank)...................: Auto
Twr2rd(Different Rank)...................: Auto
Trd2wr(Same/Diff Rank)...................: Auto
Dimm1 Clock Skew Control.................: Auto
Dimm2 Clock Skew Control.................: Auto
[B]
Channel B[/B]
Static tRead Value.......................: 11
 tRD Phase0 Adjustment...................: Auto
tRD Phase1 Adjustment....................: Auto
 tRD Phase2 Adjustment ..................: Auto
 tRD Phase3 Adjustment...................: Auto
Trd2rd(Different Rank)...................: Auto
Twr2wr(Different Rank)...................: Auto
Twr2rd(Different Rank)...................: Auto
Trd2wr(Same/Diff Rank)...................: Auto
Dimm1 Clock Skew Control.................: Auto
Dimm2 Clock Skew Control.................: Auto
[B]
Motherboard Voltage Control[/B]
CPU
CPU Vcore................................: 1.27500v
CPU Termination..........................: [COLOR=Red]1.22v[/COLOR]
CPU PLL..................................: 1.5v
CPU Reference............................: [COLOR=Red]0.757v[/COLOR]

[B]MCH/ICH[/B]
MCH Core.................................: 1.2v
MCH Reference............................: [COLOR=Red]0.752v[/COLOR]
MCH/DRAM Refence.........................: 1.050v
ICH I/O..................................: 1.5v
ICH Core.................................: 1.1v

[B]DRAM[/B]
DRAM Voltage.............................: 2.1v
DRAM Termination.........................: 1.050v
Channel A Reference......................: 1.050v
Channel B Reference......................: 1.050v

[B]Advanced Settings[/B]
Limit CPUID Max. to 3....................: Disabled
No-Execute Memory Protect................: Enabled
CPU Enhanced Halt (C1E)..................: Disabled
C2/C2E State Support.....................: Disabled
x C4/C4E State Support...................: Disabled
CPU Thermal Monitor 2(TM2) ..............: Enabled
CPU EIST Function........................: Disabled
Virtualization Technology................: Enabled

When vtt is 1.20v, and you lower the cpu ref and mch ref one step from 0.76v, it will be 0.745v and 0.740v, respectively. Then when you increase the vtt up one step from 1.20v to 1.22v, the cpu ref and mch ref will scale up from 0.745v to 0.757v and 0.740v to 0.752v respectively.

You have to try different combinations of cpu and mch ref. You may have to decrease or increase cpu ref and mch ref 1-3 steps down or up when vtt=1.20v, and then increase the vtt up to find the right gtl ref sweet spot for your hardware. Hope that helps.

Good luck.

[D-Rock]

Re: Help me OC my E8400

Okay, so when I adjust the cpu and mch reference voltages before adjusting vtt. Sounds simple enough with trial and error. How will I know when I have the cpu and mch ref adjusted correctly? Will it become stable or will that only come after i find the right vtt? I have been reading that vtt is just going to allow the fsb to be pushed farther so as long as I have a high enough vtt to support 455fsb then all I need to do is get the mch and cpu ref adjusted correctly right?

[BoombasticSloth]

Re: Help me OC my E8400

I found cpu ref, mch ref and vtt work in tandem with each other. You may have to find another gtl ref combo for each level of vtt. Based on my experience, the higher you push your vtt, the more likely I needed to lower my gtl ref voltages. I also found that with my two e8400, they liked to have the mch ref voltages lower than the cpu ref voltages. YMMV. Record your combinations in a spread sheet to help facilitate the process.

edit: For got to address this. You will know if your mch and cpu ref's are correctly when you can pass your stability test of choice.

[D-Rock]

Re: Help me OC my E8400

Awesome, thanks for the replies friends. I hope to keep getting this kind of support as my other favorite forums have severely let me down.

Seems I have got the FSB stable at 455mhz now. I kept vtt at 1.2v and the first combination of cpu ref and mch ref I tried was CPU Ref at 0.715v and MCH ref at 0.700v and that got the bus stable. I ran prime for 24 hours and it was still running great. Now tonight I will bring the multi back up to 9x and run prime until tomorrow afternoon and see if the CPU is stable there or if I need to adjust the voltages again.

Once again, THANKS for the help.

I just ask that you continue to help me until I reach my personal goal, which is a the highest safe 24/7 oc I can get. I am really hoping for around 4.5ghz. Higher would be amazing but Id really just like to get it to 4.5

[D-Rock]

Re: Help me OC my E8400

Ok, well I need some advice. I got the FSB stable at 455 with the voltages posted above. I then ran prime95 overnight with the multi at 9x and all went well. I then bumped up the FSB to 475 with the same voltages and lowered the multi to 6x to test the FSB stability again. The bus was stable after 12hrs of prime so I raised the multi back to 9x again and cranked the vcore up to 1.3v to check for CPU stability. The CPU was not stable but interestingly, core0 failed 7 minutes in and core1 was running fine 12hrs later. From what I read it sounds like a gtl voltage is not right but I wanted to check here before I continue.

What do you suggest I do?

[BoombasticSloth]

Re: Help me OC my E8400

For 475 x 9 = 4275mhz, you're going to need more cpu voltage than 1.30v. However, start increasing your vtt from 1.20v and see if prime can run longer before failing. If it runs longer, then increasing the vtt and cpu voltage is probably the route to go before making any changes to gtl.