Hi, I've never overclocked a processor before so I'm somewhat conservative about the whole thing. I don't want to mess up the CPU so that it shortens its life, I just want a highly stable overclock.

That said I'm somewhat stuck as to what to overclock. The rig I'm building will be used mostly for gaming. Since the 6600 and 8400 are pretty much the same in price and I'm getting the xigmatech 1283 hs which do you think would be the best choice after overclocking stabily?

I'm thinking the 8400 would go to 3.6 or maybe a little higher, but I hear after 3.6 you have to increase the voltage (and OC the RAM) and the temps skyrocket.

Where's a good equivilant for the 6600? Would it be worth getting the quad core for future games that will take advantage of it, or should I just stick with dual?

I ordered the Q6600 myself, for the reason that quad core will stick around longer than dual. And it stills overclocks very easily, its almost guaranteed to reach 3ghz and 3.4-3.6ghz are very do able. Plus, at these clock speeds, the CPU will not be the bottleneck in your system.

a q9450 can be OC'd to 3.6ghz with no voltage gain, you should look into that if you want

The Q9450 is $329 while the other two are below 200. I would like to keep it below $200.

How stable is 3.4? With the 1283 do you think it would be fine? If you over clock too much will it shorten the life of the processor?

Wow this is funny, I came here last night and searched for the term 8400 and read all the threads about overclocking. It was very informative.
They basically convinced me to get another Q6600 and clock it up. As I am not much of a gamer.

I picked the Q6600 myself. However, stay away from nVIdia motherboards. Just flat not having any luck on my 680i mobo. I've seen a lot of 3.4 & 3.6Ghz OC's on the Q6600, but most of those are on Intel chipset motherboards. Course you're looking at voltage changes for anything over 3Ghz on a Q6600 from the results I've read in other threads.

Keep in mind, some argue the E8400 is 'faster' in current games since most games will use dual-core but don't necessarily use all 4 cores at once. In the future though, mult-core is going to be much more common. So the quad core will eventually be faster.

4 Processors at 3Ghz > 2 Processors at 3.6Ghz (Assuming all cores are being used)

And even at stock 2.4Ghz with my Q6600, when playing Crysis or Age of Conan, it's my 8800GTS (G92) that limits me. Not my CPU. So even at stock speeds the Q6600 is perfectly fine. No bottlenecking so far as I can see.

How about temperature, I would guess that getting your 6600 up to 3.0 (that's the safe OC right?) would get much hotter than if you got your 8400 up to 3.6. From what I can tell the 8400 barely feels going up to 3.6 but once you increase the voltage the Temp skyrockets.

Also, is there something special when you have a 1:1 FSB: DRAM ratio, or does that not matter? Since if I get the 6600, going to FSB 333 for 3.0, would that mean I wouldn't need 800 RAM, just 667? In that case wouldn't the RAM be cheaper with better timings?

3,0 is a very safe overclock, temperatures won't go much higer, and it is very doable with the stock cooler. For myself I have bought a Tuniq Tower and overclocked it to 3,4 , I don't suggest clocking much higher cause you won't really need all that power. I downclocked it back to stock 2,4ghz and it is fast enough for ANYTHING. I've thrown GRID , CRYSIS , PREY, DOOM3, SUPREME COMMANDER, QUAKE 4, UT3 , AOE III , and it's all fluent. The only thing that stops me is my EVGA Geforce 8800GTS (g92) but hey, don't you just love 60+fps in everything (except crysis then) @ 1680x1050

Make sure it's an Intel motherboard, I have a P35 motherboard and it's rock stable even @ 3,6ghz! Nearly never had an error. Just make sure you apply the correct voltage and keep an eye on temperatures.

if you get a q6600, just bump the FSB to 333 and away you go, thats all you should need to do unless you are unfortunate and get a bad one

It's kinda like the pci-e 2.0 bus... improved bandwidth and more power to the pci slot, but we aren't even using 16x pci bandwidths yet(maybe sli 9800 gx2's might ???)

Done tons of comparisons (online and thru friends comps vs mine) and seems quadcore is much better for multitasking, video editing, type work! Reason being because games aren't utilizing quad, or if they do, it's usually not the big boost it should be.

Either way i myself am sold on the 8400 faster 1333 bus vs.1066, 6mb vs. 4mb l2 cache(in the cache world that's "TWO" mb more than the 6600 which will also want to split it between 4 working cores),...not to mention 3.0 ghz right out the gate.

Until i get mine, can only make guess based on reviews...0.82volts minimum (probably more like 1.20v idle) to1.36v MAX, should be plenty of room to get 4.0 ghz with good air cooling! (if it's to loud, your to old! I joke! But mine sounds like a air conditioner running)
Speaking of volts, 45nm(8400) uses less power and runs cooler then a 65nm core(6600)

Adjusting voltages isn't a bad thing as long as you monitor temp and voltages ranges while your doing it, which comes to another point!

8400 thermal junction =72.4c (YUMMY!)
6600 thermal =60c


Even without a high O.C. on the 8400, I still think the quad cores time hasn't come yet for gamers...kinda like PCI-E 2.0.

how high would someone be able to OC a q6600 or a q9450 without a voltage increase?

I'm getting a pretty good cooler for the rig (xigmatech 1283). The games I am sure to be running are: almost anything from valve, bioshock, mass effect (and any sequels), crysis and supreme commander maybe, starcraft II (definitely!). I don't think that matters too much though. I wonder if a quad core would be good enough for max settings on those games (besides crysis) to last me over until new games will utilize quad cores more effectively.

Temperatures are somewhat an issue since I will be living with no air conditioning in a sometimes 80 degree room. I don't really want a computer that will contribute massively to the heat.