I5-750 bclk 200 x 16 = 3200. Is it OK?

[AstroGuardian]

Hello there,

I am not an OC guru so that's why forums exist right?
So i have my i5-750 OCed to bclk 200, multiplier lowered to 16 (cause i have the stock cooler) and my DDR3-1333 clocked to 1200 and CPU voltage up to 1.125v but BIOS shows 1.140v

The mobo is Gigabyte P55-UD3R, so i was thinking whether or not this setup is too stressful to the motherboard. I was planning to OC to 200 x 20 when i get a new cooler in few months. CPU temps go up to 80c under CPUStress with 4 cores maxed but around 70c in real life scenarios.

What do you think about this? I am most worried not to fry anything. Should i correct something? All other voltages are set to AUTO.

Thanks

 

[Rifter]

200block is pushing the mobo to the upper limits for air cooling. That said there is still alot of mobos that will do 200 just fine so if its stable then i would say you are fine, run prime or linx for 12 hours and if you pass i would say you are good to go. Just make sure there is enough airflow over the motherboard to keep it cool, proper case airflow becomes critical when pushing the mobo to the limit. Would also recommend a aftermarket cooler, if you are on a budget a coolermaster 212+ is $30 reg price, can be had for $20 on sale and is enough to get you to 3.8-4Ghz if your cpu can do it.

 

[bryanW1995]

I would bump up the multi and lower the bclk, you only have ddr 1333 anyway. should be able to get that at 180 or so with a lower multi, will put less stress on mobo and still get you awesome performance.

 

[MadScientist]

I have mine set at 185 BCLK, 20 multiplier, 3.70 Ghz, but had to crank the vcore up to 1.325V bios to get it LinX stable. Temps are not a problem, 65C full load LinX and 60C Prime 95 blend. I've tried going higher, raising voltages, but it's not stable over 3.70 Ghz
I've got one of the first batches of i5-750s, about a year old, possibly a higher VID then the newer ones.

With a better cooler like the CM Hyper 212+ and good case ventilation you should be able to reach 4.0 Ghz.

 

[wpcoe]

FWIW, I have an i5-760 (same as yours, just 1x higher on multiplier) also on a Gigabyte P55 mobo with PC-1333 Kingston RAM. I do have the CoolerMaster Hyper 212+ HSF suggested above. I currently am configured at BCLK 166, with 22x multiplier.

I chose the 166 BCLK multiplier because I have the "ValueRam" line of Kingston RAM, which is not intended for high-end overclocking, and with a 8x RAM multiplier I can keep the RAM running at 1333. (Coincidentally, I later added another 4GB of no-name RAM which also is not ripe for overclocking.)

With the 166 BCLK, 22x multi and 8x RAM multiplier, I comfortably run a 3.65Ghz overclock. With TurboBoost and EIST (SpeedStep) enabled, I sometimes see an overclock to 4+Ghz (25x), and very often just idling at 1.5Ghz (9x).

My CPU Vcore is set to "Auto," and the highest voltage I've seen drawn while running Intel BurnTest is 1.28v, while most of the time my voltage is reported as .88-.90v.

IIRC (I can't find my notes at the moment), when running IBT my core temps peak at about 60°C, while in normal use they are only about 2-3°C above ambient room temp.

I just re-read your sig and noticed we also have the same SSD, one of the same HDDs, and Win7 Home Pro x64, so I think you could easily meet/exceed my modest overclock, once you get a 3rd party HSF. I'm pretty sure we could both comfortably overclock to 4Ghz. I'm just not all that interested in doing so.

FYI, I have dual 12cm fans on the CM H212+ HSF, in a push/pull configuration, though the "push" fan is about raised about 1cm because it overlaps the nearest (4th) RAM slot. If you only use two RAM slots, (#1 & #3 as recommended by Gigabyte), then the fan position is not an issue.

 

[toyota]

I thought i5 760 was only 21 for the multi so how did you go to 22?

 

[MadScientist]

I and the OP have 750s not 760s.

 

[toyota]

I and the OP have 750s not 760s.

look at the post directly above mine...

 

[wpcoe]

I thought i5 760 was only 21 for the multi so how did you go to 22?

BIOS lets me select 22x. There's a long explanation, which right now eludes me. Something to do with TurboBoost.

I would expect that the i5-750 BIOS (Gigabyte P55, anyway) let's them select 21, as well.

 

[toyota]

BIOS lets me select 22x. There's a long explanation, which right now eludes me. Something to do with TurboBoost.

I would expect that the i5-750 BIOS (Gigabyte P55, anyway) let's them select 21, as well.

yeah I remember something like that too now that you mention it.

 

[Kenmitch]

What are your other voltages at. You stated most on auto.

200 bclck isn't that high if stable and doesn't require high CPU vtt voltages.

 

[MadScientist]

With Turbo enabled you will get a 21 multiplier with the 750. I tried it with lower BCLKs but still could not get the system stable above 3.7 GHZ.

 

[Kenmitch]

With Turbo enabled you will get a 21 multiplier with the 750. I tried it with lower BCLKs but still could not get the system stable above 3.7 GHZ.

So you think you got a dud chip? Or you think it's the mb? 3.7ghz isn't bad.

I take it you tried higher bclck and lower multiplier to test mb.

Best I got mine to boot win7 was 4.597ghz but only for screenshot.

 

[AstroGuardian]

Thanks guys especially Kenmitch,

Since i don't want to do anything stupid i lowered the bclk to 166 which gives me memory @ 1333 and i am good with that... for now. I also bumped up the multiplier to 20 so i get 3,33ghz now. I will have to satisfy myself with that until i find LGA1156 mounts for my old Cooler master Gemini II S. I have it lapped so i might lap the cpu too.
FYI the Kingston value ram worked stable during the short try @ 200 x 20. It gave me like 20.000mbps read, write and copy in Everest 5.5 benchmarks and it was stable. It also gave me 39,9ns memory latency. I have dreamed about that kind of memory performance since the days of my Old Athlon 3500 🙂

For those who wonder why i need the drastic performance, i run @ least 3-4 virtual machines on my Windows 7. I have Server 2008 Standard R2, SQL 2008 Express, Win7, openSUSE and an XP running...

Thanks again for your suggestions. Much appreciated

 

[betasub]

^ Pretty much the same as my every-day overclock (20x167). Turbo is enabled to give poorly-threaded apps access to the higher multipliers and 4GHz goodness.

 

[Kenmitch]

^ Pretty much the same as my every-day overclock (20x167). Turbo is enabled to give poorly-threaded apps access to the higher multipliers and 4GHz goodness.

Why don't you guys use the 21x multiplier?

Currently my wifes using my rig for a web surfer 🙂

I knocked it down to 4ghz. I'm using 21x191 with speedstep and C1E enabled. My rig idles at 1.8ghz vcore 1.08v at load 4.01ghz vcore 1.34v cpu vtt 1.12v

 

[MadScientist]

Yes, I tried a 21 multiplier hoping that I could raise the BCLK to get it above 3.7 Ghz but still could not get it above 3.7 Ghz. Raising the vcore up to 1.40V didn't help. Raising VTT, PCH, and PLL voltages did not help either. I'm stuck at 3.7 Ghz. Not sure if my CPU is a crappy overclocker or it's the MB. I kept the ram underclocked and had to raise vdimm to 1.6V to get the system stable. Checked the ram with Memtest86+, no errors.

 

[Kenmitch]

Yes, I tried a 21 multiplier hoping that I could raise the BCLK to get it above 3.7 Ghz but still could not get it above 3.7 Ghz. Raising the vcore up to 1.40V didn't help. Raising VTT, PCH, and PLL voltages did not help either. I'm stuck at 3.7 Ghz. Not sure if my CPU is a crappy overclocker or it's the MB. I kept the ram underclocked and had to raise vdimm to 1.6V to get the system stable. Checked the ram with Memtest86+, no errors.

So your running 20x185 stable. But if you bump to 21x multiplier even with a lower bclk it's a no go over 3.7ghz. How high of cpu vtt did you try?

 

[betasub]

Why don't you guys use the 21x multiplier?

Since you quoted me when asking your question:

With my Asus board, to fully activate Turbo settings requires setting the default 20x multiplier in BIOS. But of course Turbo states are always available in Windows, so depending on core loading, 21x - 24x multipiers are active. It's only on boot it shows 20x.

 

[Kenmitch]

Since you quoted me when asking your question:

With my Asus board, to fully activate Turbo settings requires setting the default 20x multiplier in BIOS. But of course Turbo states are always available in Windows, so depending on core loading, 21x - 24x multipiers are active. It's only on boot it shows 20x.

Ok. On my evga mb to use 21x I need to enable c1e,speedstep,turbo mode. To kill the 24x I disable the enhanced speedstep. I figured if it needed the same vcore to stabalize it under 24x multiplier I might as well get the benefit of 4 cores instead of one 🙂

 

[betasub]

Hmm, but it only hits 24x if the load can be handled by just 1 or 2 cores. For 3 or 4 cores, we both get 21x.

 

[MadScientist]

So your running 20x185 stable. But if you bump to 21x multiplier even with a lower bclk it's a no go over 3.7ghz. How high of cpu vtt did you try?

Right now I'm running a VTT of 1.204. When the 750s first came out the Intel recommended VTT max was 1.21, so I tried to keep it slightly lower than that.

In July, 2010 Intel changed the VTT max to 1.40 (page 65) or is it 1.155 (page 67)? Which one?

http://download.intel.com/design/processor/datashts/322164.pdf

If Intel's VTT max is now 1.40 then I will try higher VTTs to try to get my 750 stable above 3.70 Ghz.

Does anyone know what software, if possible, and some say it's not, will read the VID of an i5-750. CoreTemp can't. My MB bios doesn't. I set my CPU to stock, 2.66 Ghz (20 x 133), disabled C1E, Speedstep, and C-State tech, so when it booted up it would be at stock. Using the latest version, 1.55.2 beta, of CPUZ, at stock it's reading 1.232 vcore. Is this as close to a VID reading that I'm going to get? If it is my VID it's crappy. Intel's specs state that the i5-750 VID range is 0.6500 - 1.4000.

 

[Kenmitch]

Right now I'm running a VTT of 1.204. When the 750s first came out the Intel recommended VTT max was 1.21, so I tried to keep it slightly lower than that.

In July, 2010 Intel changed the VTT max to 1.40 (page 65) or is it 1.155 (page 67)? Which one for a 750?

http://download.intel.com/design/pro...hts/322164.pdf

If Intel's VTT max is now 1.40 then I will try higher VTTs to try to get my 750 stable above 3.70 Ghz.

3.7ghz isn't a bad overclock....That's a free 1.1ghz per core 🙂

Your guess is as good as mine with the spec sheets....But I'd say max cpu vtt between 1.21-1.40v. The spec sheet also say's our i5's run @2.66ghz 🙂

You can try for a higher oveclock if you feel the need. It's just if your chip is up to it or not. You could play it semi safe and just say no cpu vtt of more than 1.275v's or so and see what you can get. I'd suggest using the 21x multiplier as it won't make a diff on voltages. Seems like higher bclk = higher vpu vtt more than anything. Not sure what your mb will do but I've tested mine up to 226 bclk. Above and she craps out. Just gotta play around and see what your chip will do. Maybe your max'd now or maybe not.

I kinda go on the philosophy that not all chips are created equal. Every chip has it's hidden potential for us to find. I also believe that you can't force an overclock with insane voltages as each chip will have it limits.

Currently mine is running at 4ghz.(191x21) loaded vcore 1.34v (+.16875v) cpu vtt 1.15v and idles at 1.7ghz vcore 1.08v which seems pretty good.

OP I figure the conversation may be of some use for ya 🙂

 

[MadScientist]

From posts on other forums they are referring to the table on page 65 of Intel's July 10, 2010 Datasheet as the new max volts for an i5-750.

VCC - 1.40 max
VTT - 1.40 max
VDDQ - 1.80 max
VCCPLL - 1.98 max
Also I read somewhere that the difference between VTT and VDDQ (VDIMM) should be <0.5V.

Yeah, 3.70 Ghz is an ok oc, and I'd like to stay at 1.204 VTT, so I may just stay where I am. IMO, my CPU's VID is probably the limiting factor.

 

[Kenmitch]

Does anyone know what software, if possible, and some say it's not, will read the VID of an i5-750. CoreTemp can't. My MB bios doesn't. I set my CPU to stock, 2.66 Ghz (20 x 133), disabled C1E, Speedstep, and C-State tech, so when it booted up it would be at stock. Using the latest version, 1.55.2 beta, of CPUZ, at stock it's reading 1.232 vcore. Is this as close to a VID reading that I'm going to get? If it is my VID it's crappy. Intel's specs state that the i5-750 VID range is 0.6500 - 1.4000.

I think to get a true idea of what the chip is requesting as far as the vid range you'd need to enable c1e,speedstep, and c-state. I'm thinking voltage was greater with the single core load 24x multiplier envoked when I tested mine.

Yeah, 3.70 Ghz is an ok oc, and I'd like to stay at 1.204 VTT, so I may just stay where I am. IMO, my CPU's VID is probably the limiting factor.

When overclocking a person needs to stay in their own comfort zone. What fun would it be if you constantly worry about voltages anyways.

I think if you wanna keep your cpu vtt where it's at and you wanna try for a higher overclock you'd need to use the 21x multiplier. If your chip doesn't respond with vcore then maybe your chip is at it's limit? Maybe a slight nudge to the cpu vtt woud help? Maybe not? I wouldn't try to force it with insane voltages to make the next jump tho!

My comfort zone is more dictated by temps than voltages with my chip. As it doesn't need alot of cpu vtt I don't have to worry about that, vcore isn't bad but even being on water these chips do get hot under full load.

VCC - 1.40 max
VTT - 1.40 max
VDDQ - 1.80 max
VCCPLL - 1.98 max
Also I read somewhere that the difference between VTT and VDDQ (VDIMM) should be <0.5V.

I've looked at those charts before and after the update. They are kinda confusing but on the other hand they are the stated specs for the chip running at stock speeds. I wouldn't suggest throwing them out the window and juicing up the chip tho. I'd think the specs are based on the laws of averages and influenced by power draw and thermal output of the chips. You have to take into consideration that all chips are not created equally and each of them will have it's limits. It's luck of the draw when it comes to overclocking 🙂

If I remember the VTT and VDDQ (VDIMM) was a socket 1366 thing wasn't it?