The first thing I see is your power supply. That PSU could die from this and end up killing your computer or worse. Please don't attempt this unless you don't mind killing this computer.

 

That will be solved soon because I will be getting a Coolermaster 600W I-Green Power PSU. I will also upgrade my GPU to a GTX 560. Do you really think that it' the PSU that is causing the MIT settings to drop back to 2.66Ghz or is there another reason?

 

I don't know. I just know that overclocking with a low-quality PSU can be dangerous. The iGreen might not be a good choice either. Judging from professional reviews, that PSU is 9 years old. I don't know if I could support using that PSU in good conscience.

When you're overclocking, your system becomes way more sensitive to the quality of the power that the PSU is delivering - especially the CPU. If that power is too unstable (too much ripple, even if it's within ATX spec) and/or too inaccurate (loose voltage regulation, even if it's within ATX spec), then you could end up with problems.

 

I know the iGreen isn't exactly an excellent choice either but I can buy it from an acquaintance for a very cheap price. A completely new 600W PSU would cost me way more. I'm willing to take the risk of overclocking this system, it's a 7 year old backup pc anyway.

Any ideas on what the cause might be of the MIT settings dropping back to 2.66Ghz as soon as I go over 3.80Ghz? Could it have something to do with the ram timings / voltages ?
Which MIT values do you recommend to reach 4Ghz on my system? I take full responsibility of doing this knowing that I could potentially kill this computer.

 

I don't know that board in particular, but I wonder if it's automatically reverting back due to being just that unstable. 3.8 GHz is a huge overclock for this, so yeah.

 

Hmm yeah true 3.80Ghz is already high but I want to push it a little higher to 4Ghz. If I burn out the chip I can always get a used one for like € 5 -10. Which settings should I adjust to make it more stable given the pictures that I provided? I don't think I can increase my Vcore even more because it is already at 1.8Volts. And when I put it at 2.0Volts which I already did once my system won't boot / goes into boot cycles and then I have to reset the CMOS with the jumper. I think my cooling is sufficient because my temps don't go so high (never above 75°C so far) it's just something else that makes the clock speed revert to 2.66Ghz

 

I don't think it's going to happen with that motherboard and this PSU. You're gonna need the EP45-UD3P and a high-end PSU for this.

I just realized that overclocking socket 775 CPUs also requires good memory.

 

I think it's possible with my GA-P35C-DS3R. Look at the top overclocks on this website. They all have Gigabyte P35 boards. Only one of them is water cooled. So it should be possible once I have my better PSU. And I have already upgraded my memory to DDR3-1333Mhz CL9 so that should be ok I think.

 

Which model of memory is it though? The speed and CAS# latency doesn't tell us anything.

The iGreen PSU probably won't deliver stable and accurate enough power to get a good stable overclock that high. I'm not trying to say that you shouldn't attempt it because you're not afraid to kill this computer, but still.

 

I posted it under my full system specs: "RAM: Corsair XMS3 4GB (2x2GB) DDR3-1333 CL9 1.5V"

I just mounted the new GPU (GTX 560) and PSU in my system and it boots. Re-mounting that huge CPU cooler wasn't fun...
Anyways going to try to overclock higher than 3.80Ghz. But I will start from 3.60Ghz at which it was stable for 8+ hours in Prime95 Blend and work my way upwards in 5Mhz increments.
Hopefully the issue of resetting itself to 2.66Ghz will now be resolved... atlhough I doubt it.

 

That board supports DDR2 and DDR3, and iirc wasn't the best board for overclocking. FSB limited.

 

Correct it supports DDR2 & DDR3 but not at the same time though. So I replaced my Apacer 4GB (2x2GB) DDR2-800 CL5 sticks with the Corsair XMS3 4GB (2x2GB) DDR3-1333 CL9 sticks in order to reach a higher overclock without going past the speed that the RAM was rated for. With the DDR2 modules I was reaching speeds like 950Mhz with the lowest possible multiplier (2.00) which is way past 800. I don't have that problem anymore with my DDR3-1333 modules but it does reset itself to 2.66Ghz as soon as I go higher than 3.80Ghz (475x8). Hopefully that will change with the new power supply. I'm stress testing now in Prime95 at stock speeds with stock voltages to see how stable my system is with the new PSU.

 

475FSB is pretty high. Supporting both DDR2 and DDR3 means you have more options but also means that it can't do either as well as a dedicated board.

Lower your CPU multi to isolate the FSB and see how high you can go using NB voltage (and other advanced tweaks if they are available). Iirc DDR2 and 1:1 FSB:RAM ratio was best combo on P35/P45. Most overclockers avoided the "C" boards when the boards were new to market.

I think I ended up at 3.8GHz 24/7 stable on the e6750 abit ip35-e (variable resistor modded) system I built for my mother in law.

Iirc 500FSB is tough to get on that board and not guaranteed.

CAS9 is a lot of latency for 1333. I'd have to have CAS6 or 7 to be satisfied. I'd use DDR2 1000 with CAS5, but getting low latency DDR2 might be hard these days. I was using the D9 DDR2 800 4-4-4-12 sticks in my P35/45 projects back in those days. They overclocked to 1250 5-5-5-15 for benchmarks, but I ran them 1150 5-5-5-15 for 24/7 use.

I'm sure there are some old threads covering this board, it's limitations, and possible ways to overcome them if you do some searching.

 

Yeah, that abit motherboard was a pretty good one.

 

So would it bet better to use my Apacer 4GB (2x2GB) DDR2-800 CL5 sticks for my overclocking endeavors?

Btw I isolated the problem: What happens is when I go over 3.80Ghz (475x8) the "CPU Host Clock Control" resets itself to [disabled].
I have advanced BIOS feautues like "CPU enhanced halt", "CPU thermal monitor 2" & "CPU EIST" already set to [disabled].
Here's a picture:


Any ideas? I mean this is overclock.net there must be someone around here who holds the key to the solution.

 

I would turn TM2 back on as it will protect your CPU from thermal damage.

Did you try reducing the CPU multi to isolate the RAM/FSB? See if you can get the FSB higher without taxing the CPU too much, and play with other BIOS settings to try and stabilize the NB. Once the NB is stable raise the CPU multi back up and focus on the CPU speed.

I would try OCing with both sets of RAM and run tests and benchmarks to see what gives the best results.

 

Ok I will turn TM2 back on. And I have tried lowering the cpu multiplier to 6x and the raising the FSB higher but as soon as I reach 3.80Ghz (635x6) the CPU host clock frequency resets itself to [disabled]. All other settings stay the same. How do I stabilize the Northbridge voltage? Do I need to increase (G)MCH OverVoltage Control for that?

 

You don't need to go that high on the FSB. Since you're back at 3.8GHz it'll be hard to tell if it's the CPU or NB holding you back.

Yes, MCH is NB voltage.

Iirc, it is tough to get 4GHz on e6750.

 

Just to put this into perspective, I had the E8400 in the EP45-UD3P, and as you know its stock speed is 3.0 GHz. Also, 1 GHz overclocks to Core2 CPUs was considered to be a big and respectful overclock. Anything above that, and you're looking at needing water cooling.

So, I had the E8400 @ 4.05 GHz and making it go higher than that with my Tuniq Tower 120 was difficult, at best. I got it to 4.2 GHz for a few minutes, but my temps were way too high, easily reaching the 90s with Prime95's Small FFTs test. The voltage had to be stupidly-high too.

In other words, I wouldn't expect much more than 3.66 GHz if you want a rock-solid stable system.

 

I would like rock-solid stability at 3.60Ghz but only a few seconds at 4Ghz just to submit a CPU-Z validation link

I'm buying a used E8400 dual core now, i'm hoping to OC it from it's stock 3.0Ghz to 4 - 4.5Ghz.
15 people pulled it off on air so I think since I invested in way better cooling I should be able to do the same.

 

Make sure it's an E0 revision. The C0s suck.

I would look at what motherboards and memory and power supplies they had though! For example:

http://us.hardware.info/usersystems/6723/black-dynomite

Look at that motherboard, look at that memory!, and look at that power supply! You can't expect to get the same overclocking performance if you have inferior parts.

 

Well that one was 4.7Ghz... if I reach 4Ghz i'd already be satisfied.

 

Well again, make sure the E8400 is an E0 revision - and as I tried to say before, please don't kill it with the iGreen. There are plenty of affordable PSUs that would be more than good enough for this.

 

But but... I just bought the I green, i'm not going to spend another € 60 on a brand new 500W PSU.

And I don't know if the E8400 is an E0 revision it doesn't say on the ad. :-/
http://www.2dehands.be/computer-game-consoles/computer-onderdelen/processors/core-2-duo-processoren-e8400-250608583.html

 

OH YES IT IS! Woo-hoo! It's the SLB9J which is the E0! Whew. Buy it!

Anyway, I would recommend returning that PSU so that you can buy a new one. It's 9 years old, man and it's very low in quality and so it will hold you back.