Overclocking Questions (i5-750)

Alex@Nosound

Member
Apr 23, 2010
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Currently

1.35v QPI
1.41vcore (bios)
PPL 1.88v
LLC - Level1 [vdrop adjusted no overvoltage on load]

BLK running 200x21 [IBT stable]

If i go any higher i get some blue screens im wondering what kind of voltages i can use for the cpu but more the qpi since i think thats the problem.
 

extra

Golden Member
Dec 18, 1999
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7
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That's some mighty high vcore you got going on ther. I'd go to 200x20 first, drop the 21 and turn turbo and speedstep off for now.

Lower vcore a little man, try 1.375. Raise the VTT. That's the key. Try 1.3V VTT, you may be able to get it to stabilize with way way less vcore.
 

Alex@Nosound

Member
Apr 23, 2010
64
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That's some mighty high vcore you got going on ther. I'd go to 200x20 first, drop the 21 and turn turbo and speedstep off for now.

Lower vcore a little man, try 1.375. Raise the VTT. That's the key. Try 1.3V VTT, you may be able to get it to stabilize with way way less vcore.

VTT(same thing as QPI on this board) =/ also turbo is off

this board lets me manualy use the turbo as a mutli in the settings for some reason though the option for tubro is actually off.
 
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Kenmitch

Diamond Member
Oct 10, 1999
8,505
2,250
136
Currently

1.35v QPI
1.41vcore (bios)
PPL 1.88v
LLC - Level1 [vdrop adjusted no overvoltage on load]

BLK running 200x21 [IBT stable]

If i go any higher i get some blue screens im wondering what kind of voltages i can use for the cpu but more the qpi since i think thats the problem.

The great debate on cpu vtt voltage still is going on....But intel states 1.21v as max on S1156 and then again states 1.40v on the xeon S1156 chips?

I would think you already have taken the memory out of the picture....As in dropped it down to the lowest divider to be safe. You can up it later after you find your max.

I'd be more concerned with core temps than the vcore voltage. Intel states a max of just over 1.50v's.

My chip in rig is running with vcore slightly higher than yours but my cpu vtt is 1.280v I'm on water so even during the hard core stress testing my hottest core just barely reaches 70*C.

What MB do you have? Maybe full system specs?
 

Alex@Nosound

Member
Apr 23, 2010
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The great debate on cpu vtt voltage still is going on....But intel states 1.21v as max on S1156 and then again states 1.40v on the xeon S1156 chips?

I would think you already have taken the memory out of the picture....As in dropped it down to the lowest divider to be safe. You can up it later after you find your max.

I'd be more concerned with core temps than the vcore voltage. Intel states a max of just over 1.50v's.

My chip in rig is running with vcore slightly higher than yours but my cpu vtt is 1.280v I'm on water so even during the hard core stress testing my hottest core just barely reaches 70*C.

What MB do you have? Maybe full system specs?

Yeah memory is running @ 1200[Stock is 1333]

thing is my friend has 1.4v VTT on his 860 though its a different cpu i'm very confused what the safe volts are as the mobo says after 1.36 it goes into purple then 1.42 into the red my CPU usually hits mid to high 80s on stressing.

i have heard some mobos just run out of steam after 200BLK =/ i hope thats not the case tbh.

it was rock solid in 05

Full specs are

i5 750 B1
Gigabyte P55 UD5
Sector 5 DDR2 2x2GB
Silverstone Strider 700w
HD5770 rev3
 
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Kenmitch

Diamond Member
Oct 10, 1999
8,505
2,250
136
Max my board would do and stay stable was 226 but took too much cpu vtt for me. Max I've booted into windows with my chip was 4.597ghz for the screenshot only.

If you wanna test it and see just drop the memory down. Drop down the multiplier and up the blk and see how high you can get it stable at. Maybe try 19x210 or 220 with current voltages and see.

Does your MB have frequency options in the bios similar to these ones.
CPU PWM Frequency : [477 Khz]
VTT PWM Frequency : [240 Khz]
DDR PWM Frequency : [240 Khz]
If so you can play with them also to see if it helps out any.

Cpu Vtt is a your on your own type of thing. I wouldn't wanna help you fry your chip :)

I kinda draw the line at 1.300v to be safe.

Your temps are up there! Might wanna rethink your cooling strategy
 

Alex@Nosound

Member
Apr 23, 2010
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Max my board would do and stay stable was 226 but took too much cpu vtt for me. Max I've booted into windows with my chip was 4.597ghz for the screenshot only.

If you wanna test it and see just drop the memory down. Drop down the multiplier and up the blk and see how high you can get it stable at. Maybe try 19x210 or 220 with current voltages and see.

Does your MB have frequency options in the bios similar to these ones.
CPU PWM Frequency : [477 Khz]
VTT PWM Frequency : [240 Khz]
DDR PWM Frequency : [240 Khz]
If so you can play with them also to see if it helps out any.

Cpu Vtt is a your on your own type of thing. I wouldn't wanna help you fry your chip :)

I kinda draw the line at 1.300v to be safe.

Your temps are up there! Might wanna rethink your cooling strategy

Yeah i'll give that ago

also i bought a titan fenrir after being recommended by a friend but damn its nothing compared to my megahalem

im waiting for the mounting kit to come in the post and hopefully it work better than the fenrir

if not ill probably run a 240 loop or something.

I think i mite lap my chip aswell hopefully that will help some.
 

Alex@Nosound

Member
Apr 23, 2010
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Right ok well after a good inspection it really looks like the QPI voltage is to blame since my "northbridge" is overheating also according to HWmonitor the Tcase temp is going over its threshhold so it looks like a need some more fans and i should be ok (still no megahalem bracket here yet =/)

thanks for the help :)