E8400 C0 on P5B Deluxe @ 4ghz with 1.33v using stock HSF =)

Hard and Confused

Sep 13, 2008
Well, been messing with this thing for the last few hours and so far I'm @ 4ghz with my E8400 C0 @ 1.33v in bios on my P5B Deluxe using the stock HSF. My temps are from 44* C idle to 72* C load says OCCT V3.0 atm using the intel stock HSF.

ATM I'm only testing OCCT in 30 - 45 min bouts untill I find the lowest stable vCore using the stock HSF then I figure when I add my Thermalright Ultima 90 and bump the vcore up a notch from the lowest stable I find tonight I should have an 8 hr+ stable 4ghz OC on a C0 stepping which is good from what I've read so far about the interweb.

Considering the previous owner said he couldn't get into windows past 3.8ghz I'm guessing he had a crappy mobo or knew the chip went higher just didn't want to say so incase someone was using a crappy mobo or something.

Before I get too giddy is this actually a good OC thus far even with my crude rush testing on this chip? I do plan to do some serious definitive testing tomorrow and Sunday I'm just wondering if I have a chance of 4ghz+ 24/7 stable before I get arround to the proper testing so I can have happy dreams tonight :)

Heres what I'm working with:

Asus P5B Deluxe Wifi with latest bios ( no pencil mod for vdroop yet )

E8400 C0 ( vid 1.28v ) @ 500x8 with 1.33v in bios ( OCCT 3.0 says 1.27v under load )

4gb kit ( 2x 2gb ) of OCZ Flex PC2 9600 @ 500mhz with 5-5-5-15 2T timings and 1.95v

Antec Neo 500w PSU ( by Seasonic : )


My voltages are as follows for the ones I changed:

vCore: 1.33v
FSB Termination: 1.3v
vNB: 1.55v ( will not boot into windows @ 1.45v )
vDimm: 2.0v


Fully [H]
Jan 20, 2004
There's no way to know for sure until you do real stability testing. 30-45 minutes is not enough to get a good idea of stability with OCCT. Also, you should use Real Temp to monitor your temperatures like I suggested in your other thread.

Hard and Confused

Sep 13, 2008
trust me I know a 30 min test isn't rock solid but it does give you an idea if an OC is salvagable. Most OC's are gonna crash within 5 - 30 mins if there is nothing you can do to help them.

But I've also had Oc's that could consistently make is 8 - 10 hrs then crash consistently within 9 - 12 hrs. I pref to run a 24hr simultaneous OCCT & Orthos/Prime test if I can but I have a hard time leaving my PC alone that long :(

The last year I've been running on 5 - 14 HR tested OC's and I did have a problem with one after a few months then realized I was almost 50mhz beyond my CPU's max limits :(

Trust me though, that 4ghz will be more properly tested under my TRU90 overnight tonight ( provided the lan party ends soon enough ).

Also keep in mind that there is system/application and game stable, then there is the ability to crunch numbers for hours on end stable.

Just because a system cannot run a day or 2 in a program like OCCT or Orthos/Prime does not mean anyone will ever see a single issue with thier system under normal daily load and games.

Heck, 50% or more of mass manufactured computers will prob not pass a 24/7 dual stress test like OCCT & Orthos but you will never ever notice a single stability issue with them throughout their life.


Oct 13, 2005
I've got my e8500 @ 3.8ghz for everyday use @ 1.24v (vid=1.25) so running undervolted.
I tried pushing it on a very cold day with my pc on the deck =) and had it at 4.4ghz @ 1.39v with a TRUE + 3000rpm fan, but i didn't want to risk higher than 1.4v. My max temps were around 50c, but i must stress very cold day and it was outside.
Im running a Asus p5k3-deluxe + 2gb corsair DDR3 1333@15xx , what i did find is that with my g-skill DDR3 ram i couldn't overclock even 1mhz, removed it and all was good, a bit strange.
Anyway ill link my benchmarks if you want to have a look:

CPU = E8500 @ 4.408ghz
Motherboard = Asus P5k3 Deluxe
Ram = Corsair 2x1gb 1333mhz DDR3
GPU/'s = Nvidia Gtx280
Cooling = Air

Geekbench score = 4929

3Dmark 03 score = 62490
http://service.futuremark.com/result...esultType= 10

3Dmark 06 score = 19007
http://service.futuremark.com/result...esultType =14

Super Pi(1m) score = 10.655

wPrime 32 score = 17.290


Limp Gawd
Nov 22, 2008
Any results from the stability testing? If stable that's pretty nice for a C0.


Jan 11, 2007
Is that my old E8400? If so you should be able to get it stable at 4.2GHz, I ran it at 3.8GHz daily just to keep the max temps below 50C. Told you its a beautiful chip :D