First i should point out that the last time i over clocked, i was OCing an Athlon XP 1700+, so its been a while, about 4 years. I also do not yet have my parts and am trying to gain a greater understanding of Over clocking the C2D E63x0. I have never messed around with voltages either. With that being said.
My question is this. Will/Should i have to change any of my voltage settings to archive the 7 x 400 goal stated above? From my understanding that ram is rated to run at 400MHz. Also from what ive gathered, the higher the voltage the 'better' things will run but, the temperatures will rise.
Im using wusy's guide along with a TomsHardware.com Guide to try and gain an understanding. In wusy's guide Part2 he says to set vDIMM: 2.2v. Does this apply in all situations? even if youre not trying to overclock your ram?
In part3, he then lists other Voltage settings/Changes.
vDIMM: 2.1v or 2.2v
Are these listed as what they should be set no matter what your overclock goal is, or as vaguely stated at the start, this is what they should be set at to reach 4.0 GHz?
If there are any articles that would help me further my understanding of voltage's, Memory, or just overclocking the C2D 6xx0 in general, please pass them along.
As always thank you very much for any help. These forums are fantastic and i really appreciate what you guys do to help!
I have an e6400 and came from an amd 3200+ XP so i hear ya on this one. I did ALOT of reading and alot of trial and error. So here is what I came up with. FIRST you want to download a few pieces of software to help you. I am not sure where I got all these but you can find them.
1) TAT from intel (Thermal Analysis Tool)
2) Prime 95
THe p965 is the easiest to overclock with so you should be set to go. I have the 975 chipset and it was easy as well. Here is the rundown of what each tool is used for.
1)TAT: gives you the temps of each core seperatly from the hottest point in the chip. It also has a load test that you can put to 100% and test each core. This is basically the equivilent of beating the pi$$ out of your chip. If it doesnt lock up here its probably getting enough juice. you will never see the temps on a 100% test on any app or game. 70 or 75% is the max you will see ever. The thing to remember is that the core 2 has 3 temp sensors. One on each core which is what TAT reads and a tcase sensor taht is what the motherboard reads. Your goal in over clocking is to keep it under 60C on full load 100%. However you can't always do this depending on what voltage you use. just keep it under 70C at all cost that is my suggestion. Although I've found the ambient temp can play a large factor. I do not have my AC on yet and it can get 5C higher than normal on a warm day. Just keep this in mind. Idle it should be under 50C once overclocked.
2)Prime95: use the torture test to test your memory and CPU. If this runs for a while with no errors you are good to go. I'd say the minimum is 20 minutes but a good hours is suggested. Some people run this for hours and i dont see the point.
3) CPU-Z: just gives you a complete readout of what speed things are running at. Good reference tool.
Ok so here is my FIRST suggest. Work on cooling before you touch anything. Get a GOOD CPU cooler. I got the Thermalright Ultra-120 and slapped on a 120mm fan. Just look on this site and anandtech at the cooler review and pick one that will keep it chilly. You will also need good case air flow. Intake and exhaust is highly suggested.
Next what you want to do is work on your CPU. Turn the divider down on your memory to keep it running the lowest speed you can so it doesnt interfere with your cpu overclocking. I would then manually set your cpu core volatage to 1.325 I think this is stock or close to it. Then just start bumping up the FSB. You are correct, your goal should be 400mhz. I dont like going over this because it strains the motherboard and its just a good goal. Stock is 266 so I'd put it to like 300. Then run The tat and 100% load for 30 seconds or so. If all is good run prime for 20 minutes. If all is good bump it up. if it fails bump up the voltage one notch. Test again. Basically I would do incriments of 25 MHZ. If it was a crazy overclock I'd say 5 or 10 mhz but your goal is VERY reasonable. You will just have to increase your voltages. Just do NOT go over 1.5V. 1.45 seems even high to acheive your goal. I run at 1.4125 to hit 400mhz on mine. once you hit your goal run a GOOD long prime to make sure. Play a quick game or something as well. Just test it out.
Then go back and try the memory. Bump it up to the DDR2 800 speed and run prime and everything at the stock volrage. You might get a reboot or something because i had to bump mine up as well. My memory is rated at 2.2V but i only needed 2.0v to keep stable. The lower the voltage the cooler it will run. I think stock on auto it is like 1.8V. But you should be able to keep it under the 2.2V stock.
And there you go. Once you are done you should be able to run a TAT for a minute or so and Prime for a good 30 -60 min run. Run a benchmark like 3dmark05 or something as well. And play some games and whatnot. If it reboots or locks up you know something is wrong and you will have to troubleshoot but that's basically what I did.
I reread your article and saw you have the ACF7 cooler. This should be good enough. I actually had/have this cooler before i went to the thermalright cooler. It was ok at my 3.0GHz speed but i had to crank the voltage up alot to hit 3.2GHZ and it ran a little warm for my liking. That's another note for you. Every Core2 has this "wall" where it seems you have to bump up the voltage significantly to get just 200mhz higher. I am seeing this alot when you go from 375mhz to 400mhz bus. It seems to be a trend so just keep it in mind and don't be alarmed. You may also want to manually set your memory settings if it is not reading correctly. Check CPUz to make sure all the timing is being picked up correctly. I know mine was not so i manually set it. Also check out the tomsharware guide to overclocking Core2's... There are alot of Motherboard settings you can disable which lighten the load on the chipset. I did this and my Motherboard temps dropped a nice bit just because it wasn't working so hard to do things i dont need.
According to one of the more interesting threads I've read in Intel's open Dev forums, a very unpleasant picture arrises. Desktop/Server CPUs DON'T have a constant Tjunction temperature, unlike many Mobile CPUs which contains the Tjunction information in bit 30 of MSR 0xEE. This value is either 85/100. Possibly by a mistake, this value seems to exist in the desktop processors as well, but this does not make it valid at all.
TAT was developed for mobile CPU usage. The whole Tjunction minus DTSDelta was good for these CPUs(with small deviations of several degrees above or below), but it is basically useless for desktop CPUs. In desktop CPUs the calculation is PROCHOT# minus DTSDelta, and obviously we cannot read PROCHOT# temp.
I have a lot of mess with temps, pictured in my several posts on THIS forum. I'm nearly sure, that there is no tool to measure these temps without proper calibration, which seems impossible. Friend of mine, who's running 2 rigs with exactly the same coolers, but with different CPUs (Prescott & Conroe) says, that with the same temp reading (60C), with the same software utilities, heatpipes above Prescott are really warm in touch, while heatpipes above Conroe are cold. Seems we are in the very beginning with proper C2D temps monitoring.
EDIT: For today, the only sure temp calibrating for C2D is to enable thermal monitor, and observe the point of PROCHOT taking action. But I don't know nobody brave enough to do it. We need volunteer...
Alright, i have read through everything here (thanks to all who have helped me out) and i then read through some other articles and have a few more questions/clarification's.
1) Jay2Tall said i should "Turn the divider down on your memory" this means i should set my system memory multiplier to: 2.00 (using DS3) and my timings to 5-5-5-15 correct?
2) If i am correct on question 1, how do i then bump my DDR2 800 back up to DDR2 800?
I still am a little unsure about the whole '1:1' concept and how the memory 'integrates' (for lack of a better word) into the overclock. Like i get that my DDR2 800 is running at 400Mhz, (or is it, is it only running as fast as my FSB)... yeah, i think thats where im kind of lost...
3) Besides locking up, how will i tell if something is 'wrong' or unstable while OCing? Is my understanding correct that Prime95 tells you in something is wrong?
Again, thanks a ton for all your help! All the help has been awesome, and fascinating as well.
DDR is Double Data Rate (i think) which means for every fsb cycle it does 2. So if you have a FSB of 400mhz the memory is running at 800mhz. Which is what the 1:1 ration means. This is optimal. There is some math behind it. My motherboard doesnt actually show the ration it just showes my memory speed settings but some show a ration you have to set. I'll try to explain.
If you are running stock on a c2d you are running 266MHz FSB. this alone in a 1:1 ratio is only 532 MHz when you double it for memory. Obviously this is slower than the ddr2 800 native speed. So you apply a divider of 4:6. If you know math to have the following
4:6 = 266:x which is bascially this:
--- = ---
SO you cross multiply the 6 x 266 = 1596 then divide by 4 = 399Mhz.
Then dont forget its DDR so you double it giving you about 798MHz. close enough to 800 right? The 1:1 ration is basically NO divider so there is less overhead. Just like if you had Super fast memory like DDR2 1066 you would give it a divider of 1:2
--- = ---
you cross multiply the 2 x 266 = 532 then divide by 1 = 532Mhz
It's DDR so x2 gives you 1064Mhz
Follow me here? The reason this is, is because the multiplier in the CPU is locked so you cant change it. Well i think you can reduce it by one. So you have to overclock the FSB which also speeds up the memory. SO you are basically juggling the FSB and divider with what works best for your CPU and memory to live happily together. The problem is like me I had a FSB of 375 running my CPU at 3GHZ but that means my memory was only running at 750Mhz. I didnt like that so i eventually got it stable to 400FSB.
And to answer the Prime 95 questions, yes it spits out an error and you will know if it fails. Just remember to overclock slowely and test each time.
I know that the divider thing is sorta confusing but most motherboards will tell you what the figured memory speed comes out to with the divider in place. Just keep it under the 800 while you are overclocking so you know it is not an issue with you trying to overclock the memory when you are tryign to oc the cpu at the same time.
@2) It will be at DDR 800 perfectly, at the moment you'll reach 400 FSB (which is rather easy). "1:1 concept" gives you an unified data bandwidth in a CPU-chipset-memory triangle. If you clock memory or chipset higher - you'll get an additonal bandwith in them only (not necessarily required), at the cost of less stability in the whole triangle.
@3) Stability tests, like Orthos or TAT will generate error or thermal throttling (without lockup) if anything fails.