Overclocking Q8300 questions

Hello everyone! This is my first post, and I'm sure it's in the right place. ;-)
Here's my story:

I recently bought two sticks of DDR2 RAM, 2GB memory each. I knew my motherboard supports

DDR2s up to 1200 MHz, so I took those Kingston HyperX 1066 sticks. Mounted them onto my board and launched the PC. Everything was running fine on automatic settings - 800 MHz 1,8V. I googled the right values for my memory to work in 1066 mode, rebooted my computer and entered BIOS.

What I changed was:
Memory mode (or however it's called in my BIOS) -> DDR2-1066
Memory voltage -> 2.2V
and I manually entered timings -> 5-5-5-15
after that I saved settings and rebooted my PC.

POST screen kindly informed me that I was running 1066 MHz 4GB RAM. OS booted without a problem and everything was going really smooth till I launched Starcraft 2 and began an online play.
Game started to freeze every three seconds for about half a second, which was very annoying. Without thinking too much I downloaded Memtest86+ and made a bootable flash drive; I rebooted my PC and started testing memory.
I didn't like the test results at all. Memtest gave me plenty of errors. To make sure the sticks were OK I switched back to DDR2-800 mode and to auto-timings and voltage and re-ran the test. I came back after six hours and there were absolutely no errors.

I was like: wtf?

I sent the sticks back to the store I bought them, asking to exchange them for another pair. What they told me after two weeks of waiting was the memory seemed to be OK and they were sending it back to me.

I started to look for another solution.

I found a couple of articles and posts which said that frequency that memory runs at is somehow connected to the CPU's FSB (or something like that). What I understood from the texts was: if you want to have your RAM running on 1066 MHz, you need to overclock your CPU a bit.

And that's where the fun began.

I think this is the moment when I should tell you my system spec.:

Intel Core2Quad Q8300 CPU
Asus P5Q Pro motherboard (latest bios)
2x2GB Kingston HyperX 1066 DDR2 (KHX8500D2K2/4G)
Asus GeForce 7600GT Silent
PCIe SATA-RAID controller
PCIe ESI ESP1010e soundcard
3x SATA 320GB HDD
400W Chieftec PSU
Windows 7 x64


I got my sticks back today and plugged them in right away. Since I had some time to google things up I've already knew (more or less) what other settings should I change to make my RAM cooperate with CPU correctly.

I changed FSB from 333 to 400 MHz along with RAM mode from 800 to 1066 (with all the timings and voltage). I disabled all power-saving features of my CPU and also disabled Fan control to keep it at full speed all the time (I use a factory cooler).

In fact, increase of the FSB was an only change I made to my CPU.

I saved settings and rebooted. Went through POST and Windows loaded without any problems. I launched CPU-Z to see my current CPU speed, then brought HWMonitor onto my screen to finally make 'Small FFTs' test in Prime95.

Unfortenately I had to cancel it due to growing CPU temperature.



Are such high core temperatures normal when using a factory cooler with slightly increased FSB?
In safe mode (factory settings) temperatures are 44-50'C.

you didn't do any volt mods to the vcore did you?
id try a different temp monitoring software if i were you, hw monitor has given me false readings many many times...

I'd use 'Real Temp' ... some people have had nothing but problems out of HW monito and some people swear by it... try them both out... I tend to keep a close eye on my temps and I'm barely OC'd .. only a small 3.8G on my i7 920....I run around 47C when playing SC2 on high.. soooo.. hmmmmm....

Well, I installed Real Temp and turns out the temperatures are the same as those shown in HWMonitor. This saddens me...

I wrote down CPU temperatures when decreasing voltage, these are my notes:

V in BIOS : V in CPU-Z : temp ['C])
Auto (1,3625V) : [did not write down] : 90-95
1,3000V : [did not write down] : 86-93
1,2875V : (1,280) : 85-92
1,2687V : (1,264) : 85-92
1,25V : (1,24) : 81-88
1,225V : (1,216) : 76-84
1,1875V : (1,176) : 73-80
1,15V : (1,136) : 71-78

Just after I managed to get the temp below 80 degrees, I tried to do "In-place large FFTs" test with Prime. Unfortenately it gives me errors within first 10 seconds of testing.

Increasing FSB voltage and North Bridge voltage didn't help. I'm afraid the CPU voltage is too low, but if I increase it again it will result in my PC getting on fire.

What should I do?

your gonna need an aftermarket cooler. i have a q8300 on my girlfriends pc i got it upto 3.5 stable with 1.35v and the ram set at something weird between 1066 and 1333

with the little mascool 92mm cooler i have to use because of her tiny case it still ran at only 70c max w. prime95

i didnt try to change the votlage any though im sure it coul have ran lower but i was just cranking it up to see how it would oc with the new ram in it.

Damn it. I changed my RAM settings back to Auto so they work in 800 MHz mode and guess what? I get NO errors with Prime.
Does it mean my RAM really is broken?

Oh, I'd like to add that when I OCed my CPU with ~1,325V and Vfsb 1,45V and put the chassis outside my window where the temperature is -7'C at the moment, core temps weren't so high and prime was working for pretty long without errors.

I'm so consufed. Is it my RAM broken, or is it just about finding a proper voltages? : (

re seat the cpu, change the thermal paste
if using stock heatsink get a high end one
my contac 29 is not bad at all, im doing 1.4 vcore on my q6600 to do 3.4 and max temp i got was 60C on core 1, im still working on lowering voltages
and that is with just 1 fan on the heatsink

I ordered Scythe Samurai ZZ for my CPU as I don't believe in my factory cooler's capabilities. I should receive it by wednesday and we'll see what change that will bring.

I'll keep you guys posted.

Good deal

Uh-oh. The new cooler decreased core temperatures a lot, but I'm still unable to get my system stable with my memory running @ 1066.
I tried setting different timings, RAM, NB and other voltages, but it didn't work. Whatever I do I get errors when running 1066 DDR2.
What should I do?

try declocking them to 800
you wouldn't see too uch performance difference from 1066 and 800

Well, yeah, I know, but if I wanted them to run @ 800 I wouldn't spend extra money on memory that is able to run @ 1066, right?

The CPU however works perfectly with the new cooling!
I'm currently testing its stability @ 400 MHz 1,25V and so far it's been running for quite long without errors. The highest temperature does not exceed 61'C (with the stock cooler it used to reach 88'C).
I'm not gonna try and push it further, because silence is what matters to me the most. I'm gonna set my fan speed control in BIOS to 'silent' mode now and we'll see how are the temperatures when doing the high-priority stuff: mixing audio in Sonar with lots of real-time plugins enabled. If I hear the CPU fan increase its speed to a level which could disturb me, I'll have to underclock my Quad or lower its voltage to minimum...
But we'll see about that.

What still bothers me is my memory. Yeah, I know I wouldn't even probably see the difference between 800 and 1066, but it's like driving a Lamborghini in town with top speed limited to 50km/h. And yes, you should not drive faster than 50km/h in town, but still... how would ya feel?