• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

i5 750 @ 4 GHz Any tips ?

Associate
Joined
30 Dec 2008
Posts
669
Location
SCOTLAND
Any i5 750 users running on a Gigabyte UD5 ?

Just upgraded yesterday.

Had it running @ 4.2 GHz with 1.4vcore, I used some settings from here.

I want to settle on 4 GHz with voltages as low as possible.

I also got 2X2 GB sticks of G.Skill ECO which i obviously want to run as best i can however, I have absolutely no clue about memory especially DDR3.

Here is what i have at the moment, I can post VTT/PCH values if needed.

2i5311.jpg


Intel Core i5 750

Gigabyte GA-P55-UD5

G.Skill ECO - F3-12800CL7D-4GBECO

Thermalright ULTRA 120

Corsair HX650 PSU
 
Associate
OP
Joined
30 Dec 2008
Posts
669
Location
SCOTLAND
Looks like you can adjust some of the timings.
Speed is correct - 800 x 2 = 1600mhz.

Yeah, I was wondering if the DDR3 RAM runs 1:1 with the BCLK ?

Never saw any settings for it (Or i didn't understand them)

Set vdimm to 1.4Vish and set timings to 7,7,7,20, 88

I was a bit unsure when it had that RAM @ 1.5x when i first booted in.

Cheers mate, Will do, Be back in a tick.
 
Associate
OP
Joined
30 Dec 2008
Posts
669
Location
SCOTLAND
208d56b.jpg



QPI Clock Ratio [Auto]
Sys Memory Multi (SPD) [6.0]
PCIE Frequency [Auto]
CIA2 [Disabled]
CPU Clock Drive [800mv]
PCIE Clock Drive [800mv]
Clock Skew [0ps]
=======================================
Memory
=======================================
Performance Enhance [Turbo]
Dram Timing Selectable [Quick]
Profile DDR Voltage [1.5v]
Profile QPI Voltage [1.1v]
Channel Interleave 6 [Auto]
Rank Interleave 4 [Auto]

Load Line Calibration [Level 2]
CPU Vcore [1.375v]
QPI/VTT Voltage [1.2v]
PCH Core [1.12v]
CPU PLL [1.8v]
DRAM Voltage [1.4v]

All Others [Auto]


Would not boot at Load Line Calibration Level 1.
 
Associate
OP
Joined
30 Dec 2008
Posts
669
Location
SCOTLAND
Tried with 8 and BSOD, Upped the DRAM Voltage to 1.5v Still BSOD.

Back to 6.

I have managed to boot @ 8-8-8-24/88 with 8X Memory Multiplier.

Command is 1T, Does this make any difference ? I normally see peoples at 2T.
 
Last edited:
Soldato
Joined
18 Oct 2002
Posts
5,381
Same system bar the cooler and max i can go is 4.1, with the F8 bios you can go up to 21 multi although i think that just forces turbo mode even though its on already.
 
Associate
OP
Joined
30 Dec 2008
Posts
669
Location
SCOTLAND
Same system bar the cooler and max i can go is 4.1, with the F8 bios you can go up to 21 multi although i think that just forces turbo mode even though its on already.

Aye, 21 multi is turbo on one or two cores ?

Can you post your voltages mate ?

What temps are you getting ?

I can hit 80C running prime, I don't want to try LinX :D
 
Associate
Joined
13 May 2009
Posts
803
Location
Glasgow
I've just put my 750 to 4GHz too and all seems stable (only 10 mins into a Prime blend). I'm using slightly different RAM from you, the blue G.Skill Ripjaw stuff rated at 8-8-8-24 2T, but I can get mine to boot with LLC level 1. Try 1.5v for the RAM that might work.
 
Associate
Joined
26 Feb 2010
Posts
34
i can get my i5 750 to 3.8ghx 181X21 complete stable. This is with 1.20 vcore

but when i try to up tp 4 ghz its breaking my brains now. Its not stable even with 1.25 vcore.

Can it be my ram? OCZ 2x2gb 8-8-8-24 1.65 volts, but my motherboard can only insert 1.64 or 1.66 volts.

Gigabyte P55 US3L.

Any recomendations would help thanks
 
Joined
5 Aug 2006
Posts
11,306
Location
Derbyshire
i can get my i5 750 to 3.8ghx 181X21 complete stable. This is with 1.20 vcore

but when i try to up tp 4 ghz its breaking my brains now. Its not stable even with 1.25 vcore.

Can it be my ram? OCZ 2x2gb 8-8-8-24 1.65 volts, but my motherboard can only insert 1.64 or 1.66 volts.

Gigabyte P55 US3L.

Any recomendations would help thanks

iirc the i5 750 default votage is 1.25volts (please don't quote me on that though). A 4ghz overclock is likely to need 1.3-1.45 volts.

I am currently overclocking my i5 750 on a Gigabyte UD3R tonight. Afaik it is identical to your board in terms of overclocking.
I am at 3.8ghz on stock volts at the moment
Also don't set cpu volts to auto as the board will overvolt it.

Please ignore my sig right now.
 
Associate
Joined
26 Feb 2010
Posts
34
My 3.8 ghz is complete stable at 1.20 volts, so thats why i run it.

Now trying this and will volts up until its stable. Fingers crossed wont be too high.

4.00 Ghz 200X20 multiplier 8 so ram is at 1600 Mhz at 1.64volts

Vcore at 1.25Volts

I will report how long it lasts

Thx
 
Joined
5 Aug 2006
Posts
11,306
Location
Derbyshire
My 3.8 ghz is complete stable at 1.20 volts, so thats why i run it.

Now trying this and will volts up until its stable. Fingers crossed wont be too high.

4.00 Ghz 200X20 multiplier 8 so ram is at 1600 Mhz at 1.64volts

Vcore at 1.25Volts

I will report how long it lasts

Thx

I just started prime (4 threads) 5 mins ago at 1.27 volts or something like that.
Running 200x20 = 4ghz. Ram at 1600mhz at the manufacturer's rated voltage.

male sure you enable load line calibration in the bios to counteract vdroop.
My stock voltage of 1.25v failed prime after 5 minutes. This isn't too concerning as I just upped the volts a touch and trying again. If prime fails after 10 seconds then your pc is miles and miles away from stable!

Now at 10 mins stable:).....
 
Soldato
Joined
16 Oct 2009
Posts
8,917
Location
Essex
iirc the i5 750 default votage is 1.25volts (please don't quote me on that though). A 4ghz overclock is likely to need 1.3-1.45 volts.

I am currently overclocking my i5 750 on a Gigabyte UD3R tonight. Afaik it is identical to your board in terms of overclocking.
I am at 3.8ghz on stock volts at the moment
Also don't set cpu volts to auto as the board will overvolt it.

Please ignore my sig right now.

My Core i5 has a default voltage of 1.20625 V (at least this is what my mobo tells me). I have plenty of problems overclocking it to higher frequencies than 3.8GHz (and am not happy with high voltages applied to achieve this too).

Don't know how LLC works with Gigabyte boards but my MSI GD65 have significant voltage spikes with it, thus I don't apply anything over 1.35 V with Low Vdroop. Overclocking with LLC enabled is a whole different thing than when it's off.

With High Vdroop (LLC off) I get pretty bad voltage drops, about 0.072 V difference between idle and load.

I'm wondering what you mean by stock volts. If you only leave your V-core at 1.25 V and have LLC on plus you tweak your VTT to achieve this, I can assume it may be stable. Otherwise I could not imagine this as my CPU requires a lot of tweaking to get stable with 3.8GHz overclock...
 
Soldato
Joined
16 Oct 2009
Posts
8,917
Location
Essex
My 3.8 ghz is complete stable at 1.20 volts, so thats why i run it.

Now trying this and will volts up until its stable. Fingers crossed wont be too high.

4.00 Ghz 200X20 multiplier 8 so ram is at 1600 Mhz at 1.64volts

Vcore at 1.25Volts

I will report how long it lasts

Thx

Can you run 20 loops of IntelBurnTest (LynX) with custom stress level using max RAM - 200MB? If it's stable and you can do Futuremark Vantage or some proper stressful gaming, report it back. I found prime95 to be of a little use if you have less than 8h to stress your CPU. My system did freeze whilst watching a movie even though it was stable under heavy load for many hours during variety of tests.

Let me know of VTT voltages you apply along with DRAM voltages. They seem to be as important as a v-core in some cases.
 
Joined
5 Aug 2006
Posts
11,306
Location
Derbyshire
My Core i5 has a default voltage of 1.20625 V (at least this is what my mobo tells me). I have plenty of problems overclocking it to higher frequencies than 3.8GHz (and am not happy with high voltages applied to achieve this too).

Don't know how LLC works with Gigabyte boards but my MSI GD65 have significant voltage spikes with it, thus I don't apply anything over 1.35 V with Low Vdroop. Overclocking with LLC enabled is a whole different thing than when it's off.

With High Vdroop (LLC off) I get pretty bad voltage drops, about 0.072 V difference between idle and load.

I'm wondering what you mean by stock volts. If you only leave your V-core at 1.25 V and have LLC on plus you tweak your VTT to achieve this, I can assume it may be stable. Otherwise I could not imagine this as my CPU requires a lot of tweaking to get stable with 3.8GHz overclock...

I am using the LLL as it increases vcore under load, rather than giving my cpu a higher voltage 24/7. Gigabyte have a very good range of P55 boards out and the one I bought has 12 phase power (however this could just be a marketing point and not be of much real world use).
 
Back
Top Bottom