It is now clear that current E6600s are not the overclockers' dream

[lopri]

From the day Conroe was 'previewed', many overclockers have dreamed of running E6600 overclocked to 3.6GHz or even to 4.0GHz. Apparently the E6600's charm was and is the 4MB L2 cache and the lower price than other 4MB cousins, as well as the X9 multiplier that'd perfectly mate with 400FSB and DDR2-800 to make 3.6GHz.

Now that E6600s' availability is somewhat reasonable I've seen many results and frustration from many folks along with that of other models of Conroe/Allendale. Everything I've seen, including my personal experience, tells me it's time to 'get real' with regard to your expectation.

http://www.xtremesystems.org/forums/showthread.php?t=113006
http://www.hardforum.com/showthread.php?t=1075792&page=1&pp=20

Above examples are just a few of many others. 3.6GHz, not to mention 4.0GHz, with the current batch of E6600s is a luck of draw. The chance of stable 3.6GHz with an E6600 is very small, to say the least, and even though you get there the cost (voltages) isn't cheap.

On top of that, personally I've experienced numerous problems while maintaining my now-sold-E6600 @3.6GHz. It's basically about performance/stability inconsistency. From the look of current situation, it seems like E6600s are left-over from X6800/E6700 binning, and E6300/E6400 are clocking higher than E6600 thanks to its smaller L2 cache and probably less aggressive binning.

So my advice for overclockers: If you want to enjoy high clocks with less frustration and less stress on your hardware, go with E6300/E6400 and P965. If you have to have the best even at cost, go with E6700/X6800 and 975X. Avoid E6600 if you can.

 

[Conky]

I was sold on the E6600 and just about to throw down but have decided on a E6400 instead.

Retailers are still gouging for the E6600 and even at stock speeds the E6400 is no slouch and overclocked on even the cheapest motherboards(which my tight ass is considering) brings you to E6600 levels with little effort and with better motherboards/RAM brings you into the same ballpark as the E6700/6800 or higher.

I thought about the E6300 too but even with a minor overclock it's still only up to the E6400 which seems to be the overclocker's choice right now.

I've always liked to go with the overclockers choice... P2-300 running at 504Mhz, my Celeron 566@850, my Northword 1.8a running at 2.4Ghz, and recently stopped a couple years ago at my Northwood 3.06 running smooth at 3.45 with HT for just too darn long.

I'm about to pull the pin and get that E6400 tonight... one more :beer: until I hit the "purchase now" button. :laugh:

 

[n7]

Yeah my dreams of 975 + E6600 quickly changed when i realized what was happening.

Now i should be getting my E6400 + P5B Deluxe tomorrow, all going well anyway

Just the wait for the RAM will be a while...

 

[Baked]

Ouch, the E6600 is like the ass of the bunch. I bought a E6400 w/ DS3 and some DDR2 800. All I'm wishing for is 8x400, nothing more.

Do you think th manufacturing week has anything to do w/ the OC capability?

 

[Conky]

Originally posted by: Baked
Ouch, the E6600 is like the ass of the bunch. I bought a E6400 w/ DS3 and some DDR2 800. All I'm wishing for is 8x400, nothing more.

Do you think th manufacturing week has anything to do w/ the OC capability?

That should be pretty do-able with the right set-up.

I just ordered an E6400 and an ASRock dual board... yeah, I should be limited to 2.4 gigs or so but once I have the cashflow to buy a better board and some good DDR2 RAM then all bets are off.

 

[Polish3d]

I don't know, my E6600 is at 3.45ghz with almost no increase in voltages and I'm on high end air. I suspect it could hit 3.6ghz rather easily with the right mobo. I haven't even really pushed it yet.

 

[neuralnut]

8 x 400 is straightforward with a 6400, but getting higher and staying stable is not easy. I have two 6400s running at 3.2 GHz stable 24/7, but have not had any luck beyond that. I got as high as 420 x 8 on the better of the two machines, but it was too flakey for real work, so I have dropped back to conservative settings.

It is nice though that a 50% overclock can be considered conservative.

 

[tylerw13]

i would totally agree with you lopri my e6600 is quite crap....it doesnt get passed 3.3 with out uppin the voltage a ton i should have gotten a e6400 or a e6700...oh well such is life

 

[Pabster]

Yeah, the 6600 is such a POS. ROFL

The fact is that people got their hopes up too high with ES chips doing 3.6+ constantly on air.

I've been thrilled with my 6600's.

 

[the Chase]

Thanks for the heads up lopri. I see you went with the 6700 and hit 3.6 Ghz. Are you happier with this chip? Are you topped out at 3.6? Do you think it's worth the extra $? In your experience can you scrimp on the motherboard with this chip since it has the 10x multi?

Sorry for the inquisition style questions but thanks in advance and also for your other input/threads on these CPU's.

P.S. What are your thoughts on the temps that a lot of people seem to be getting (esp. with some added volts) with these chips? Wrong reporting or just high temps? I'm really starting to lean towards the idea that these CPU's run quite hot- and get really hot when adding volts.

Also the concave IHS? What were your two CPU's heat spreader's like? Did/would you lap them?

 

[Henny]

1 Ghz of pure OC on a new E6600 ain't too shabby and I'd hardly not call it an "overclocker's dream". However I think best bang for the buck is probably E6300 or E6400 and a 965 MB like P5B.

If I had to do it over again I'd probably go P5B and E6400 instead of P5W DH and E6600 but I'm not complaining.

 

[smopoim86]

I also originally wanted a 6600, but i'm really leaning toward a 6400 now, cheaper and better OC

I still think that the drawback right now is the mobos

 

[zephyrprime]

The 6600 kinda sucks right now for overclocking but I bet that with a few steppings, it will be a much better overclocker.

 

[TraumaRN]

Originally posted by: zephyrprime
The 6600 kinda sucks right now for overclocking but I bet that with a few steppings, it will be a much better overclocker.

Ya when they arent being raped cuz of speed binning and whatnot.

 

[Zap]

At the most recent LAN that I attended (hosted by chicagogamers.com) someone had an E6300 on an Asus 975X board and was only able to get around 2.6GHz "easily" with no vcore. Could get a bit above that but vcore needed to be boosted more and more.

I'm gonna still wait for an E4300 with a cheap 965 board (isn't there an overclockable Gigabyte for around $120?).

 

[lopri]

Originally posted by: the Chase
Thanks for the heads up lopri. I see you went with the 6700 and hit 3.6 Ghz. Are you happier with this chip? Are you topped out at 3.6? Do you think it's worth the extra $? In your experience can you scrimp on the motherboard with this chip since it has the 10x multi?

Sorry for the inquisition style questions but thanks in advance and also for your other input/threads on these CPU's.

P.S. What are your thoughts on the temps that a lot of people seem to be getting (esp. with some added volts) with these chips? Wrong reporting or just high temps? I'm really starting to lean towards the idea that these CPU's run quite hot- and get really hot when adding volts.

Also the concave IHS? What were your two CPU's heat spreader's like? Did/would you lap them?

Hi,
I will try to answer your questions as much as I can. But please keep in mind it's my personal experience + observation.

First, I definitely feel more comfortable with the E6700 than E6600. For 3.6GHz E6600 required 1.57V+ voltages. Even that, I wasn't sure if it's truly stable. It's mostly like motherboard is to blame, but say, if you're able to finish dual Prime95 for 6 hours when you try it again you'd expect it to last at least 30 mins. Sometimes it failed in 10 secs, sometimes it ran fine, sometimes it failed 3DMark05 but 3DMark06 ran forever, etc. I just couldn't find a comfortable overclock. It was extremely inconsistent.

With the E6700, 3.6GHz is consistently stable and I can boot up to 4.0GHz @1.6V. That is of course for a couple testing and E6600 simulation (in order to get 9x400 using CrystalCPUID I had to boot @10x400 first), in no way I'd give 1.6Vcore with air-cooling. My only complaint is that this board (P5W-DH) doesn't allow multiplier adjustment so I can't run 9x400 to maximize the performance. Other than that, E6700 would be definitely my choice over E6600.

From what I've heard, P965 chipset are still having problems with these 4MB L2 cache chips. If you don't want to wait, I'd suggest you pick a 975X board for an E6700.

As far as temp reading is concerned, I've grown to trust CoreTemp more than anything else. Do I hate to see the high temperatures than what ASUS Probe reads? You bet. But After much fooling around (undervolting, underclocking, running fanless, and of course overclocking), my conclusion is that only the readings from CoreTemp make sense. Check below.

http://img90.imageshack.us/my.php?image=undervoltrd3.png
http://img166.imageshack.us/my.php?image=fanlessrd0.png

When I had an E6300, I undervolted the Vcore to 1.225V (lowest my board allows. It drops to 1.19~1.20V under load) and ran dual Prime95 LargeFFT. Max temps were only 39C. So I went on to removed the fan and kept running Prime only with the heatsink. Max temp = 46C. All the while the BIOS was reporting 18~19C idle temp and ASUS Probe reported 32~33C load temp. I can't think a piece of working sillicon running cooler than ambient air. Various experiment made me trust CoreTemp, but many people don't. So I suggest you experiment with your system. Currently my E6700 loads 66C according to CoreTemp.

Last but not the least, I tend to use somewhat generous ammount of TIM when mounting HSF than the ammount I used to use for A64 mounting. To be honest the contact between IHS and HSF of C2D is horrible. I always double check before I screw the HSF. (just lift it up after sitting it on IHS and see how the contact is) Bad contact can explain up to 20C difference in CoreTemp reading from my experience.

Hope this helps. Good luck with your build!

 

[lopri]

And here is the screenshot of E6700 @3.6GHz.

http://img174.imageshack.us/my.php?image=tempmi4.png

 

[MikeR397]

Agreed. E6600 is not the overclockers "dream," at least compared to it's expectations....but...800-1000mhz is a solid overclock, especially with 4mb L2 cache. Even though i can only get 3.2ghz stable with reasonable voltages (with E6600), I think the extra 100 paid was worth it. Even if I can only say, hell, i've got 4mb L2 cache (well shared), but you get the point. Maybe it's serves no purpose (goign from the E6400 to E6600) in some instances, but it's peace of mind that I've get the current highest end tier (4mb L2) processor. AND that processor is running significantly faster than the $1,200 X6800 (well...pending the X6800 is not overcloccked). Still a good feeling.

 

[lopri]

The L2 cache definitely plays a bigger role with C2D than with A64. I'd rate the effect on performance as follow (Assuming memory:FSB is at least 1:1):

CPU Frequency > L2 Cache > FSB > Memory Frequency and/or Timing

 

[Pabster]

Originally posted by: lopri
The L2 cache definitely plays a bigger role with C2D than with A64. I'd rate the effect on performance as follow (Assuming memory:FSB is at least 1:1):

CPU Frequency > L2 Cache > FSB > Memory Frequency and/or Timing

Yes. For example, at an equal clock speed, a 4MB cache chip will run something like Pifast or SuperPI faster than the 2MB Allendale. The extreme FSB of the latter is no match for the cache in certain situations.

 

[the Chase]

Thanks for the detailed response. Nice OC and your temps are not too bad. I'll have to wrestle with going cheaper with a 6400/P965 or going for it with a 6700/975x combo now......

 

[Madellga]

I tried both E6600 and E6400. Same mobo, ram, everything.

I could reach 3.2GHz with low VCore (1.38V) with the E6400 (8x400) - 16 hours Prime95 stable and counting...

I could reach 3.0GHz with low VCore (1.40V) with the E6600 (8x375) - also Prime95 stable.

For the said 5-10% advantage on the E6600, I guess the extra 200MHz made the E6400 close the gap.

And it was 100$ cheaper. In my case the E6400 was a Win-Win situation: cheaper and good performer.

The E6600 is long gone....

 

[Madellga]

Originally posted by: Beachboy

Originally posted by: Baked
Ouch, the E6600 is like the ass of the bunch. I bought a E6400 w/ DS3 and some DDR2 800. All I'm wishing for is 8x400, nothing more.

Do you think th manufacturing week has anything to do w/ the OC capability?

That should be pretty do-able with the right set-up.

I just ordered an E6400 and an ASRock dual board... yeah, I should be limited to 2.4 gigs or so but once I have the cashflow to buy a better board and some good DDR2 RAM then all bets are off.

Which one did you get? The one with the ATI chipset goes all the way to 340FSB. That should give you some o/c room. Look at my 2nd rig

 

[Kwint Sommer]

Originally posted by: lopri
So my advice for overclockers: If you want to enjoy high clocks with less frustration and less stress on your hardware, go with E6300/E6400....

Just a thought, to get to say 3.2ghz you would have to run an E6300 at a lot higher FSB than an E6600 so wouldn't that be putting a lot more stress on your system?

 

[MikeR397]

Kwint Summer, Yes. The E6300 has a 7x multiplier i believe, which means you would need 457 fsb to get to 3.2ghz, which is a lot of stress on the motherboard and ram (unless you have the DDR 1000). This is a very high fsb and very few motherboards can get there with a reasonable mch voltage and with decent temps. However, with an 8x mulitiplier, the 6400 could easily get to 3.2 ghz with only a 400 ghz, which either the p5w deluxe or ds3 should be able to ge to without much difficulty. At that speed, you're around the max a e6600 will do, albiet with 4mb L2 cache instead of 2mb.

Just a personal recomendation... the E6600 is still the better value. Save the extra 100 bucks on buying Cas 5 instead of Cas 4 or 3 ram for your conroe rig. With 4mb L2 cache, the latencies make a small difference. I've got Corsair XMS DDR 800 that can be ran at 5-5-5-12 or 4-4-4-10 at DDR800 speeds with 2.1v (within the warrenty region by corsair) and when benchmarking, I see a very small increase with Cas 4. It is much more noticable to just overclock the ram faster (to DDR 933 with 2.1v) than fsb to gain performance with the conroe chips. That is my experience at least.