Overclocking E8400 w/ DDR2 1066

Alright guys, so this would be my first time overclocking a computer, so I'm a bit confused as to which settings I should use. I want to get to somewhere around 3.6 (or the highest without changing voltages). I've seen that for most people it's just a matter of changing the FSB to 400 and memory ratio to 1:1 since they use DDR2 800, but I'm using 1066 so I'm not sure if I should bump up the FSB to match the memory at 533mhz and just lower the multiplier, or downclock the memory to DDR2 800. But if I downclocked the memory I would also have to change the voltages for it (something I don't want to mess with)

So:

CPU Multiplier: 7
FSB: 533mhz
Memory: 533mhz
1:1
3.73ghz

or

CPU Multi: 9
FSB: 400
Memory: 400 (downclocked)
1:1
3.60ghz

Which would be better? I want to make sure I'm getting everything out of what I paid for so I'm kinda leaning towards the first so I can take advantage of my memory's ability to go up to 533mhz. Am I understanding how it works? Or is there a flaw in my logic?

E8400
2x2gb Mushkin DDR2 1066 5-5-5-15
Gigabyte UD3R

Welcome to O/C Forums

I would go with Option #1. You'll get a nice performance overall with a low multi/high FSB mix.

Just be sure you keep the vcore below the 1.36v mark and keep your temps in check.


I've got my E3110 running 8x525 with 2.2v on the ram and 1.32v on the chip. With realtemp my temps idle @ 30c and loads up to 39-42c and handles evrything beautifully

If I try the 9 ( default multi) and go above the 500 I somehow need more vcore to get the same speed Guess the 8 multi is the cherry spot.

I tried the first one out, started up but it failed prime95 after around 10 minutes. But for some reason it was locked at a 6 multiplier @ 3.1ghz instead of 3.7 how it should have been. So I went back into my bios and loaded the "optimized defaults" - now when I start it up it only goes to 2.0ghz (6*333mhz) - even under load. I know speedstep lowers it to 6x, but only under idle. Anyone know what could be wrong?

How about an FSB of 424 MHz w/ a 8.5x multiplier for an effective 3.60 GHz clock. Use a 4:5 (266/667) NB strap for an effective DRAM frequency of 1060 MHz at default timings (5-5-5-15) and Vdimm.

- 3.6ghz (9 * 400) - vcore auto - wouldn't boot up (think I had the wrong ratio)
- 3.7ghz (7*533) with vcore on auto (cpuz reporting 1.4v..), started up but failed P95 instantly
- 3.4ghz (8.5*400) vcore at 1.25, testing right now, seems stable. I chose 2.66D in the gigabyte bios for the memory multiplier, and cpuz reports that i have a 3:4 fsb:dram ratio. But now it says 5-7-7-24 in cpuz for CAS latency, tRCD, tRP, tRAS where before it was 5-5-5-15. Did I do anything wrong?

At an FSB of 400 MHz and a 2.66 D strap, the resulting DRAM frequency is 1064 MHz. Just manually change both tRCD and tRP to 5, and tRAS to 15 for a resulting 5-5-5-15.

Why such low goals? Go for 4ghz!

445x9 and run a 5:6 divider. Ram will run @ 1068mhz giving you full speed there plus you hit your 4ghz Its fairly easy to do w/ these chips.

Your board can plenty support it and if you have an E0 step, your voltage bump will be very minimal most likely.

I can run 445x9 @ 1.33v with my C0.

Well I don't really need it.. I only game on the weekends and I don't do much else that would require a faster processor. I really just wanted to run it at 1:1 since I heard it would give me the most performance. But at least I got closer to it (3:4) better than what I had before (I think) of 5:8.

But I checked the timings and they were already at 5-5-5-15 -- when I started it back up they were still at 5-7-7-24. I noticed the voltage for the memory was at 1.8v so I changed it to 2.040 -- maybe I need to bump it up just a bit?

Also, once I get everything stable hopefully, do I lower the vcore until it becomes unstable? Right now I have it at 1.25v (cpuz says 1.216) - not sure if that's above or below what other people have it for 3.6.