Vista - Help Overclocking & Rounding Errors

OK, so I need a little help here. I know the basics to overclocking. but I'm having problems.

I have a Q6700 Quad Core 2.66

Right now I'm at 3.5 GHz with good temps of 38C Idle.

So Here's my problem. I Run Prime 95 to make sure my system is stable. but either something is wrong. or that program is not stable itself.

My Computer is completely stable and passes Hours of Prime at 3.1 GHz and at 3.33 GHz yet for some reason no matter what I do. it Fails within minutes on 3.2 GHz. Then it's completely stable and passes at 3.4 but it fails within minutes at 3.5, 3.55 and at 3.6 and at 3.6 two of the cores fail instead of one.. I get the Same Error everytime it does happen to fail. It's the Rounding Error. It says Error Rounding was 0.5 when expected less than 0.4 I don't know what that means. or how to stop this from happening. So if anyone could please help me figure this out I'd really appreciate it. and ya ya why not stay at 3.4 GHz. well I will probably use that for my 24/7 speed. but I want to have the option to be stable at 3.6 or so for Benchmarks and what not.. at 3.6 I can play games perfectly fine, benchmark and what not. but I can't pass Prime95..

Idea's are very much wanted..

Thanks!

I'm not sure I'd call your situation a "problem". 3.4GHz quad guys go to the back of the problem line.

If you just want to pass prime at 3.6 then I'd say your only "problem" is most likely insufficient vcore.

Might be a voltage issue - since we have the same mobo basically, I have a weird one - at my 3.375 speeds I get BSODs whenever I come out of sleep - but i I bump it down to 3.21 (1428 FSB) the machine works flawlessly.

I have all the voltages in the green, but maxed to the green, except my RAM - it s rated at 2.1 but I am running at 1000 and 2.0 without any problems. I next plan on bumping the RAM from 1000 to 1066 since that is what it is rated at , but I haven't had time for the tests...at least not until I get an OS that boots a lot faster / has a lot less running....

lmfao - Fumz, not only were we typing at the same time, we were thinking the same thing....

lol ya ya I know. It's not much of a PROBLEM.. more as me just being picky.

and if your all in Green still then I'm higher than you.. I was at stock clocks all the way to 3.1 also. but at 3.2 and above I changed them. right now at 3.5 Ghz I have volts set to 1.40 and I heard thats pretty high as some hit 3.8 or higher at that voltage on Q6700.. and I know I have a good chip because the VID.. so I'm not really sure. I could try going to 1.45 but I don't wanna go to much higher than that. even tho temps are still great. at 3.625 my temps were idle around 40C even that was stable in all ways but Prime.. so I'm pretty stumped. as everyone will ask. are you Prime stable. so technically I'm not. but I'm at 3.5 right now. and I've been at 3.5 for a good 5 days and not one problem, not one freeze or crash or anything. but for some reason wont pass Prime. very irritating.. but hardly a "Problem"

lol sorry

It doesn't really matter that your idle temps are in the 40's, what matters is your load temps, which will increase exponentially as vcore is increase. I'd stick to 1.4v and under.

My guess is that your "problem" (lol, i still have a hard time with that one) is related to the strap dividers. The gist of it is that there's a sweet spot near each strap and as you move away from one towards the next, performance decreases, then increases again as you get near the next sweet spot. This explains why you fail at 3.2GHz, but are smooth at 3.4GHz.

You may never pass Prime at 3.6GHz without adding so much vcore that it's just not worth it? But again... to the back of the line with you!

I am beginning to realize I might have a weird / faulty CPU. Currently, I have a lot running and I have the following temps:

47-48
49-50
39-40
42-43

That Core2 is really acting strange. There is really no reason it should be that far off the mark.

So, that means I either have a bad contact problem from heatsink to CPU or else I have a faulty CPU....

Hmmm - or else a faulty sensor in CoreTemp - I fired up the nVidia System monitor and it shows

49-50
50-51
42-43
44-45

So is it no that far out. Interestingly enough, after firing up the nVidia System monitor CoreTemp shows a 4-5 degree increase in that Core2 also. It is still lagging behind cores 0 and 1 but is almost acting like it is trying to stay in line with Core3 now....

Here are all the voltages and specs and temps:

not sure, my brothers machine I built does the same thing as yours.. I've seen people with a core always 6 below and they said it's fine. So I'm not sure about that.

and Fumz, it's not that I "Just" wanna pass prime, it's the fact that like right now I'm at 3.66 GHz and everything works fine, I can play games. I tried Crysis and GRID, I can do benchmarks. and everything is fine, no freezing. nothing. yet I can't pass prime. This speed is completely stable in "MY" eyes. but it fails Prime within seconds. thats where I'm confused. and my Load temp with 2 Primes running is 62-64C so pretty close to my personal limit of 65C and below is ok. So everything is fine, Volts are fine. but Prime is hating me. so I just wanna know if this is ok to run, or if I need to be somewhere that Prime is ok with. thats all.

and as for the dividers.. thats the one area I'm not to familiar with. I don't know much. other than that at 10x Multi thats stock my divider was like 7:9 at 3.4 GHz but now that I'm at a 9x400 Multi my divider is 1:1

so not sure what the deal is. or how I can get it stable.. I know I'm a back of the line problem. but I just wanna get a Mid decent speed to pass Prime. and I will be more than happy. like 3.5 or 3.55 or 3.6 LOL

here's the thing - I turned off that nVidia System monitor, and now coretemp is showing the following:



I personally think it has a hand in why my system goes goofunky at 3.375 - as you can see from the previous posts you know what my voltages are....

Perhaps I am over-volting *too* far with my setup when trying to crank up the FSB?

well i hate to break this to you.. but you have one of the worse made Q6600's. according to Information gathered and statistics.

HM. lets put it this way. in core temp, that bottom thing. says VID of 1.325
Thats bad, that basically means to get your CPU to run at it's default speed of 2.44 it needs 1.325 v to achieve that. other Q6600's VID are 1.2875, or 1.250 and such. that makes a big difference. as the more you OC the higher it goes. so yours is that high at default. witch means you will reach unsafe "Long Term" volts like 1.55 much sooner than the average Overclocker.. so to be honest with you. I'd not go any higher than 3.1 or 3.2 GHz on that. keep it to 1.4 or 1.45 at the most. some people have reported having a VID of 1.225 and thats great.. those are 4 GHz clockers easy. My Q6700 has a VID of 1.2875 and mine about slightly better than average john. the average people's are around 1.290 or above. my brothers is a 1.265 and I wanna steal it. I might one day.. hehe He'd never know. but some people are lucky and have lower.. Look up "Q6600 VID" in google and you will find threads about it. and people posting Charts with the CPU VID and it's stable oc LIMIT..

your VID is one of the highest I've seen.. Sorry to tell ya. These days people have been buying there CPU's based on batch number and VID number. so if you ever get one used they look for that.. will you do me a favor and take a screenshot of CPU-Z main screen with that high a OC.. and post that for me.

Oh and I've also now been getting my CPU to be completely stable at 3.4 GHz with a 9x Multi instead of 10x. with a 10x multi my divider was like 7:9 and with a 9x multi it's 1:1 and that means it's workin perfectly in sync. thats why I'm passing.. So question Fumz, how do I get it to do this at 3.6 lol

I've been running prime for the last 40 minutes with no problems.. and I'll let it continue for at least 2 more hours hoping for the best.

You won't be able to enter the machine in any OC database unless you're 8 hours Prime stable, true; however, how important is that? I think you've already answered your own question? I like to be Prime stable too, but if there's one thing I find more important than being Prime stable, it's game stable. As long as I can do everything and anything I want to with the machine, then I consider it stable. At that point I stop tweaking it and start enjoying it.

I understand completely wanting to get over that last hurdle... it's now a matter of principle... Have you read this yet? Lots of good stuff to help you get over that last little bump: Howto: Overclock C2q (quads) And C2d (duals) - A Guide V1.7 - OverclockersClub Forums

Being in sync doesn't mean anything anymore. In sync, out of sync, what ever gets you the highest clocks is what counts.