Overclocking Escapades: Intel socket LGA775 Core 2 Duo E8400 E0 stepping

[Tech Tweaker]

Well, after my rather disappointing overclock of an E8400 C0 (seen here) I thought I would see what my E8400 E0 CPU can do.

Thus far, I am more impressed by the performance of this E8400 E0 CPU.

Intel Core 2 Duo E8400 E0 #1 overclock settings
VID: 1.2625v
Stock (3GHz 333x9): 1.1v (1.13125v)
3.1GHz: 1.1v (1.13125v)
3.2GHz: 1.1v (1.13125v)
3.3GHz: 1.1v (1.13125v)
3.4GHz: 1.1v (1.13125v)
3.5GHz: 1.1v (1.13750v)
3.6GHz: 1.26v (1.3v)-EP45-UD3P 1.16V (1.18125V)-EVGA 780i SLI
3.7GHz: 1.16V (1.18125V)-EVGA 780i SLI
3.8GHz: 1.16V (1.18125V)-EVGA 780i SLI
3.9GHz: 1.192v (1.2125v)-EVGA 780i SLI
4GHz: 1.208v (1.225v)-EVGA 780i SLI
4.1GHz: 1.232-1.24v (1.25625v)-EVGA 780i SLI

Intel Core 2 Duo E8400 E0 #2 overclock settings
VID: 1.25v
Stock (3GHz 333x9): 1.1v (1.1375v)-EP45-UD3P
3.5GHz: 1.152v (1.175v)-EP45-UD3P
3.6GHz: 1.152-1.168v (1.1875v)-EP45-UD3P
3.7GHz: 1.20v (1.225v)-EP45-UD3P
3.8GHz: 1.216v (1.25v)-EP45-UD3P
3.9GHz: 1.248v (1.28125v)-EP45-UD3P
4.0GHz: 1.28v (1.3125v)-EP45-UD3P
4.2GHz: 1.36v (1.3875v) 56°C-EP45-UD3P
4.3GHz: 1.392v (1.425v) 59°C-EP45-UD3P
4.4GHz: 1.44v (1.4625v) 61°C-not fully stable, good for benchmarks though-EP45-UD3P

I tested each of these overclock settings for 2-4+ hours with the Prime95 blend test and found them to be stable with no errors or warnings.

Now testing 3.5GHz: 1.1v (1.13750v) for stability, and it's been running for almost three hours now with no problems.

It seems as though this particular E8400 could have easily been branded as an E8600 CPU (even at less than stock voltage), shame the multiplier is locked at 9x maximum.

 

[Silver_Pharaoh]

Seems like a good chip right now

 

[unclewebb]

Stop wasting time. An E8400 E0 stepping should have no problem running at 4 GHz.

Bump the MHz way up and then give it enough voltage until it is stable. I seem to recall that a setting of 450 MHz x 9.0 was a nice 24/7 type setting for the E8400.

 

[PolRoger]

Back in the day... I had a very nice sample E0 8400 that would do 500x9 with less volts then my E8600's to run @ 4.5.

 

[Tech Tweaker]

Stop wasting time. An E8400 E0 stepping should have no problem running at 4 GHz.

Bump the MHz way up and then give it enough voltage until it is stable. I seem to recall that a setting of 450 MHz x 9.0 was a nice 24/7 type setting for the E8400.

That's not how I do things here.

I want to find out the amount of voltage needed for each 100MHz boost in speed.

I know this E8400 E0 can run at 4GHz, because I did it with another board. But I wanted to fully test it with this new board to find the necessary settings for this setup.

 

[EarthDog]

That's OCD yo!

 

[(G{in}[AK)TION]]

really like the results your getting. let us know when you reach 4ghz and post a cpuz screenshot of it i do like hardware pictures.

things were going great for my E0 e8400. then things started to mess up after 3 days. i had mch at 1.325, fsb at 1.250, vcore at 1.30, and the cpu speed at 3.60ghz.

now i cant get it to be stable again...what board are you using tweaker? i think i might buy the same brand or model you are using.

 

[OptyTrooper]

My 8400 E0: http://valid.canardpc.com/pzl6tc

 

[(G{in}[AK)TION]]

My 8400 E0: http://valid.canardpc.com/pzl6tc

EDITED

respect points to you sir +1

-anyway-

for me, getting the e8400 i have to 4ghz is some obsession of mine. i could stay up for hours and hours trying to reach that speed. i dont know if my life would be easier to overclock on a x38 board since it uses ddr2 memory and im using ddr3 to overclock.

 

[Tech Tweaker]

Well, it seems there might be something wrong with this EP45-UD3P I have. It absolutely stops being stable past 400MHz FSB. I've got the CPU termination (FSB) voltage boosted to 1.36v and the MCH Core voltage at 1.3v, with CPU vCore up at 1.5v (tried every setting from 1.4-1.5v) and it still won't make it to the OS.

Can't get past 3.6GHz with this E8400 on this board. The same E8400 ran at 4.0GHz on an Intel DX48BT2 with 1.45v, and was stable.

Can't be heat, I've got fans pointed at all heatsinks and other parts that might get hot and I'm using the same CPU heatsink now as when I got the CPU to 4GHz.

 

[EarthDog]

Lower the multi ion the CPU and make sure its the FSB that is the issue.

 

[(G{in}[AK)TION]]

tech tweaker, did you try swapping memory?

according to intel, they say that the max voltage this cpu can handle is 1.36v.

or was it 1.4v? also, i did not have to do any vcore raising until now with the e8400 i have. but even wtih that, i cannot stablize the cpu.

did i mention that i overclocking my e8400 as well right now?

 

[Tech Tweaker]

Lower the multi ion the CPU and make sure its the FSB that is the issue.

It's definitely the FSB.

I have the CPU at lowest multi (6x), and memory at lowest multi (2x aka 1:1) and I still can't get it stable past 400MHz. Won't even boot up if I go past 415MHz.

tech tweaker, did you try swapping memory?

according to intel, they say that the max voltage this cpu can handle is 1.36v.

or was it 1.4v? also, i did not have to do any vcore raising until now with the e8400 i have. but even wtih that, i cannot stablize the cpu.

did i mention that i overclocking my e8400 as well right now?

That's just the VID specification (1.3625v), it's not the maximum rated voltage. Max safe voltage for a 45nm Wolfdale CPU with air cooling is 1.45-1.5v for benching, depending upon who you ask. Safe 24/7 voltage is more like 1.4v (or around there, say 1.38-1.42v).

 

[(G{in}[AK)TION]]

so i could just raise the cpu voltage and start overclocking from there?

 

[EarthDog]

Try the FSB strap at 333 instead of 400.

Also, that 1:1 means your memory is running below/at its spec, yes?

 

[Tech Tweaker]

Try the FSB strap at 333 instead of 400.

Also, that 1:1 means your memory is running below/at its spec, yes?

I did, it didn't help.

Memory is DDR2-1066 Crucial Ballistix .16FD3, so yes, below spec.

 

[Tech Tweaker]

so i could just raise the cpu voltage and start overclocking from there?

Yes, there should be no problem if you have good cooling on the CPU and Northbridge to handle the increased heat from the higher voltage and overclock.

 

[doz]

What board are you running? Some boards like more NBv than others. Also, some boards will be picky about NB strap (333 vs 400).

And again, dont be scared of voltage. There is still my old e8400 in service that ran @ 1.5v+ on water @ 4.5ghz. Still chugging at 1.376 @ 4ghz. Temps need to be controlled is all.

 

[Tech Tweaker]

What board are you running? Some boards like more NBv than others. Also, some boards will be picky about NB strap (333 vs 400).

And again, dont be scared of voltage. There is still my old e8400 in service that ran @ 1.5v+ on water @ 4.5ghz. Still chugging at 1.376 @ 4ghz. Temps need to be controlled is all.

Gigabyte GA-EP45-UD3P

 

[doz]

What are all your setting? If I remember right, NBv needs to be about 1.3v maybe a little more on that board for it to be happy with higher FSB. Try raising that, run the 333mhz strap, just use a 1:1 ratio on your ram (itll be underclocked but eliminate the possibility for problems) and ensure your ram is set to proper voltage spec (2.1v maybe?).