New Q6600

[pscout]

Originally Posted by Asspigeon

I have having some problems with my voltages and multiplier. CPUZ seems to be waffling between a 6x multiplier and a 9x multiplier (set to 9x in bios). Also my CPU voltage seems to be different depending on where I check, CPUZ and EasyTune5 are showing different voltages.

I originally set the FSB to 320 but received a bsod when I started Prime95. This is confusing because my CPU & System temps were both 46c when it happened, which I thought was a decent temp.

You need to go into the advanced setting and turn of C1E and EIST when overclocking.

Those options are for saving power and reducing heat when the rig is idle ... they drop the volts and reduce the multi as you are observing.

Not sure if you can OC much with them on since i don't think you can set vc with them enabled.

I always turn them off since every rig i have runs 100% folding 724 so then serve no useful purpose for me, and severely limit your oc.

These setting are the same on my ds3r, ds3l and ds2r and 965-ds3's. I expect they are the same on all current giga mobos that oc since it is a feature of the intel cpu's they all support. C1E and EIST have been around since pentium D's and I think most of the prescotts too.

[Asspigeon]

I can't seem to get my FSB above 310. As soon as I set it to 320 or 330 I can't even boot into the bios. This is weird because my temps are low (never above 46) and 310 appears to be rock solid. I am letting the mobo do the volts and memory for the moment.

310 x 9 = 2790mhz

I will leave Prime95 running while I sleep and hopefully I can squeeze a bit more from it tomorrow. If anyone has any ideas about how to get it going a little faster please post.

[Cptn Vortex]

Try 350 x 8. It is probably the board being silly. Some hate 9X multi's.

[Asspigeon]

Well my original overclock lasted all night doing Prime95 so at least I know it is stable. Changing the multiplier to 8 didn't help. I even tried booting at 340 x 8 = 2720 and nothing.

[cadaveca]

Well, reading through the thread, it sounds as though you have not adjusted ram speed? So, when you up the FSB, you up the ram speed as well. If you look at your last screenshot, your ram is @ 900mhz.

That there reaper ram isn't known to overclock all that well. it will go a bit, but...

So, in bios, you need to change a few things. Dropping the ram divider will probably let you get a bit further...

What board do you have exactly?

[Asspigeon]

Gigabyte GA-P35-DS3R

[cadaveca]

Yeah, so do you know how to adjust this? That would be the first place to start. Your attempt at a lower multi but same cpu speed kinda confirms this.

So, lower the ram divider, then up the FSB more and see what happens. Also, if you have the "4-4-4-12, 1T" Reapers, don't be afraid to give them 2.2v...or a bit more...just make sure they are getting good airflow for more than 2.2v!

[Asspigeon]

Excellent that solved it, I just booted at 330 x 9 = 2970. I am running Prime95 again and am still seeing CPU temps in the mid 40s. I left it on all last night and woke up to 46 (I love this cooler - Tuniq Tower).

Noob question inc: Do I want to set my system memory multiplier high or low for best performance? I booted successfully at 2.5 and I'm not sure where to go from here. My memory is of the DDR2800 variety and runs on timings of 5-5-5-15.

My second question is what are the pros/cons of lowering the CPU clock ratio? I currently have mine set to the stock 9 but I know lowering it has an effect on the memory (more bandwidth?). Do I want it as high as possible or as low as possible and why?

[pscout]

I have a a ds3r with a q6600 G0 running at 365x9 with mushkin 6400 memory at 4:5 ratio (= 912) with 4-5-4-11 stock timings @ 2.2V.

Settings:
- vc = 1.35 (vdoop results in speedfan/cpuz showing 1.24V under load)
- vMch = +.3
- vfsb = +.2

- C1E and EIST are disabled.
- VT is enabled since i am running vmware on it with 2 linux vms each folding 724 for more than a month now.

My initial oc was running at 370x9 with the same settings but during some hot days it would reboot probably due to high nb temps, so i lowered fsb to 365 and it has been stable ever since.

Once you find your max stable oc for the cpu with memory at 1:1, then you try to raise your memory speed. For foldingm, maximizing memory bandwidth is my objective, so higher memory speed is more important than tight timings. If you like to get high benchmark scores, tighter timings might be beneficial.

Finding a sweet spot when vc is at a miniumum, temps are lowest, and performance of your favoured application(s) is the best involves experimentation, testing and measurment to find the best mix for you. Lowering the multi means you need a higher fsb and this will affect both cpu oc setting and memory.

For me, it is easy (but time consuming) to measure the performance of my favoured application (folding) since I can repeat the exact same workload repeatedly with different settings and measure its performance (time per frame) as well as power consumption and temperatures. If you are only gaming, then use one of the game based benchmark tools that most closely resembles your game.

[cadaveca]

Originally Posted by Asspigeon

Noob question inc: Do I want to set my system memory multiplier high or low for best performance? I booted successfully at 2.5 and I'm not sure where to go from here. My memory is of the DDR2800 variety and runs on timings of 5-5-5-15.?

well, ideally you'll hit 9x 400 for 3.6ghz. with this speed, it's best to have ram run @ 1:1, as it'll take a bigger pounding from 3.6ghz than 2.4ghz, nevermind that ratios that are not 1:1 add a bit of latency as each cycle then has to be converted to match ramspeed from FSB speed(ie 4:5=20 cycles before sync, so only one of 20 cycles is as fast as it could be)

Originally Posted by Asspigeon

My second question is what are the pros/cons of lowering the CPU clock ratio? I currently have mine set to the stock 9 but I know lowering it has an effect on the memory (more bandwidth?). Do I want it as high as possible or as low as possible and why?

There are NO cons, and many pros. multiplier is the number of pusles within each FSB clock tick...so in 400mhz, there are 9 pulses for each tick, totalling the equivalent of 3.6ghz. Of course, as you can image, as the frequncy of the ticks goes up, the harder it can be for the chipset to read them, so lessening the number of pulses in each tick actually makes the workload a bit easier for the chipset. going back to multipliers, it works kinda the same way...the lesser the multiplier, the more often a clock in sync happens, and the greater the bandwidth because of this.

400/9=44.4
450/8=56.25
515/7=73.57


and so on...