i5 750 Overclocking Issue

[Mr. K6]

So I've been fooling around with this i5 system a bit for the last two weeks. I haven't really been able to push it since I'm on the stock intel cooler (which is an utter piece of crap, wow has their quality gone down). Anyway, I've been running different configurations with 200BCLK because I'm shooting for 4.0GHz (200x20) once I can get my Noctua NH-U9B installed. Currently I'm running the CPU at 3.4GHz (17x200) with 1.1625V Vcore and 1.23V VTT. The problem is I can't enable the more advanced power saving states (C4, C6, C7 I think, they're all grouped under one option my BIOS) otherwise the system will freeze once getting into Vista.

I originally thought the problem was my VTT was too low (after comparing it with other overclocks, especially from "official" reviews). I think cranked it all the way to 1.33V, and while this allowed me to finally pass the green Vista loading bar, I still froze on the desktop, so I don't think that's the issue, although it does seem related. Also, cranking the voltage just to turn it down seems counterproductive . I don't think it's CPU clock related, as the issue still occurs at 3.0GHz (200x15). I haven't fine-tuned it, but pretty much soon after I clock over stock speeds (2.66GHz), these states will fail. I'm guessing it has something to do with the high BCLK clock, which I need to run my RAM at 2.0GHz (200x10). C1E and EIST are both enabled and I haven't had any problems, I would just like to enable these last power saving options if possible as the cooler, the better, due to my small case.

So, does anyone have any experience with this or any suggestions to try out? The other thing that crossed my mind was that this is a BIOS issue and I'll have to wait for Gigabyte to come out with something new (currently using the F4h BIOS).

Thanks,
Mr. K6

 

[rpchip]

I'm not sure but I think I read somewhere last week that if you are overclocking you can't enable c4, c5, c6 energy saving.

 

[Mr. K6]

I'm not sure but I think I read somewhere last week that if you are overclocking you can't enable c4, c5, c6 energy saving.

Seems like it's the case, but I thought maybe there was a setting I was missing.

 

[LittlePud]

Careful, AFAIK the VTT tolerance for LGA1156 is much much lower than LGA1336.

http://www.overclock.net/intel-cpus/572217-lynnfield-owners-aware-low-vtt-voltage.html
http://i255.photobucket.com/albums/hh156/inferno129/lynnfieldabsmaxvolts-1.png

 

[Warden]

Correct me if I'm wrong but isn't the standard Vcore on the i5 about 1.26? You say you are running your Vcore at 1.1625 yet just about every article I have read shows Vcore while OCing the i5 to be in the 1.3-1.+ range. I know for me personally I had a hard time maintaining stability at 3.5ghz until I pushed the Vcore into the 1.35 range. I'm currently running 3.8ghz with 100% stability and temps in the 60 degree range under full load. I haven't pushed it any further but I have 2 new fans coming for my Noctura so I may go for 4.0ghz when they arrive.

Warden

 

[Mr. K6]

Careful, AFAIK the VTT tolerance for LGA1156 is much much lower than LGA1336.

http://www.overclock.net/intel-cpus/572217-lynnfield-owners-aware-low-vtt-voltage.html
http://i255.photobucket.com/albums/hh156/inferno129/lynnfieldabsmaxvolts-1.png

Ah, great find. That's a substantial difference from i7 - thanks!

Correct me if I'm wrong but isn't the standard Vcore on the i5 about 1.26? You say you are running your Vcore at 1.1625 yet just about every article I have read shows Vcore while OCing the i5 to be in the 1.3-1.+ range. I know for me personally I had a hard time maintaining stability at 3.5ghz until I pushed the Vcore into the 1.35 range. I'm currently running 3.8ghz with 100% stability and temps in the 60 degree range under full load. I haven't pushed it any further but I have 2 new fans coming for my Noctura so I may go for 4.0ghz when they arrive.

Warden

This seems to be a decent overclocker of a CPU if that's the case. 3.4GHz is perfectly stable at 1.1625V, might even be stable at 1.15V (didn't really stress test). I got the mounting hardware to install my U9B this weekend, so I'll be able to really push it and see soon .

 

[Hoonis]

I was getting around 3.3 pretty easily with a freezer7 (slightly better than intel stock cooler). Is the Noctua NH-U12P SE2 the one to get for this chip? I've seen sandra scores closer to 4ghz, but I always wonder what the full story is/what components used etc.

 

[Mav451]

Agree on the vcore...it can go much higher, so be sure it's not vcore that's holding back your OC at this point. Btw...what BIOS are you guys with the Gigabyte boards using? I'm on the Aug 2009 (F2) and even when turbo is enabled and working I can't select the 21x multi in BIOS. The impression I got from reviews is that the 21x was actually selectable, at least from other boards (e.g. Asus).

Entering Windows, CPU-Z shows me at 21x, but Windows and SetFSB show me at 20x. It's kind of weird.

@Warden - are you doing 4x 2GB sticks of DDR3? I remember someone having to pump alot of VTT when all 4 DIMMs were filled.

 

[Warden]

I'm running 4 sticks and I haven't touched my VTT. The sticks are rated at 7-7-7-24@1600 but I have had stability issues running at that setting. I'm running them at 8-8-8-24 with no issues though.

Warden

 

[Mr. K6]

I was getting around 3.3 pretty easily with a freezer7 (slightly better than intel stock cooler). Is the Noctua NH-U12P SE2 the one to get for this chip? I've seen sandra scores closer to 4ghz, but I always wonder what the full story is/what components used etc.

I actually have the U9B (92mm version) because my case is so small. If I could have fit it, I would have used my lapped TRUE. You can probably push the chip past 3.3GHz, what was your Vcore and what other settings were you using? I'll post full results later this weekend if you're interested, but I'm aiming for 4.0GHz (200x2) hopefully under 1.3V.

Agree on the vcore...it can go much higher, so be sure it's not vcore that's holding back your OC at this point. Btw...what BIOS are you guys with the Gigabyte boards using? I'm on the Aug 2009 (F2) and even when turbo is enabled and working I can't select the 21x multi in BIOS. The impression I got from reviews is that the 21x was actually selectable, at least from other boards (e.g. Asus).

Entering Windows, CPU-Z shows me at 21x, but Windows and SetFSB show me at 20x. It's kind of weird.

I don't know if this was directed at me, but I know for sure my overclock isn't voltage limited simply because I haven't pushed it. Due to the crap stock cooler, I really can't go further than 3.4GHz without having high load temps (80C, right now I load at 60-65C depending on the app, higher in prime95). I'm using the F4h BIOS with no issues, but I don't have the 21x multiplier either (which is fine for me, because I have to run 200 BCLK if I want to run my RAM at 2000MHz). If I remember correctly, Gigabyte stated that they haven't added in the 21x multiplier in the BIOS because it's not always stable or something.

 

[Mav451]

Damn, see I'm just wondering if I'm really at 21X in the first place. I enabled Turbo and disabled the EIST/C1/etc. power saving options. CPU-Z says 21x, but Windows/Steam/SetFSB all say otherwise...

 

[LittlePud]

If you have a Noctua cooler, double check that you have it mounted properly (with the correct holes with the backplate/base retention clips in the correct orientation).