Help me overclock my phenom II 720 be

[jadawgis732]

so, I've achieved a what I would call stable overclock of 3.6 Ghz (200FSB x 18 x 1.475vcore) (Stock is 200x14x1.325) on my gigabyte ma-770-ud3 (770NB 700SB) board. I know I can go higher, but the problem is I will get random restarts if I start to do anything that requires stress on the system for over a minute. I now have it at 212x17x1.425. that is stable and doesn't go over 45 Degrees C. (idle 29). The ones that fail do so at about 55°C for the CPU, 56 for the System CPU temp. I am not sure whether I need different RAM, different board, different voltage, or this is just as high as it will go. I assume it's not the latter. I can change voltages on my Northbridge, southbridge, and obviously ram as well. I have g.skill 4gb (2x2gb) Pc28500 at ddr800 (5-5-5-15.) 1066 was fine, but I wanted to be able to rule the RAM out as a source of the problem should the overclock fail. For me to achieve 1066 I had to up the voltage to 2.0 from 1.8. Where shall I go from here. vantage tends to conk out mid 2nd test on the failing oc's. Thanks for all your help guys.

 

[napalmb]

I hope you don't mind my asking, but what kind of cooling are you using on your system? You OC temps are cooler than my stock temps.

 

[jadawgis732]

lol a rebranded coolermaster hsf 92mm....lemme check.
COOLER MASTER RR-CCH-P912-GP 92mm Sleeve CPU Cooler 21.99
I bought it at best buy with rocketfish packaging but under the rocketifish sticker you can see coolermaster in the fan's plastic.
I found that the case air flow makes a bigger difference as well as good arctic silver #5.
Also my prob was using the 1 and 3 slots for ram. someone on the newegg motherboard review page said to do that. it resulted in my memory being single channel rather than dual. now i have my cpu at 203 x 18 @ 1.456 vCore for 3.654Ghz

 

[jadawgis732]

oh and my high temps are 51c idle 36

 

[Gryphyn]

I'll join you in your crusade, jadawgis. Those temps are about what I'm getting on my X3 720, and I'm in the same boat. I can't figure out why I'm not getting a better OC.

Gigabyte GA_MA790FXT-UD5P with F5c bios, 2x2GB OCZ Reaper DDR3 1800 Memory (clocked down to 1600). Antec 900 case, Corsair TX850 PSU, Tuniq Tower 120 cooler. Radeon 4890, X-fi soundcard. Raid 0.

Though I haven't tried any higher, I can boot into and run tasks in windows (XP 32bit), and run 3dmark06 all the way up to 19x multiplier (3.8 Ghz). However, stressing the cpu with prime95 or OCCT bluescreens me with a "Machine Check Exception." My temps at 3.8 Ghz with 1.50v never went above 50C at 100% load.

I've dialed it back a little and tried 3.7 Ghz at 1.475 v, same result. 3.6 Ghz at 1.45 volts, same result. Heck, at 3.6, my load temps were like 40C. Given, it was cold yesterday.

I've run a few passes on my memory with Memtest86+, and it passes with no errors. I haven't messed with the bus speeds at all, been tweaking multiplier only. One thing I had thought of was my memory is in channel 1 instead of ch.0, because the Reaper heatpipes are so tall they don't clear the Tuniq tower. I thought that might be adding a bit of instability, but I don't really think so.

I've tried leaving the Ram voltage settings on "auto" in the bios, also tried 1.9v per the package, and a 1.8 undervolt due to the lower than spec speeds...they run fine no matter what.

If 3.5Ghz is my stable OC, that's still 25% which is respectable, but with good cooling and my components, I really expected a bit more from this chip.

Any ideas?

 

[jadawgis732]

k, first, (this will be short, I'll reply with a longer response later) 1.425 is good enough for 3.6 (200x18) I've found that HT speed at 1.6Ghz doesn't have a huge effect on performance, but allows a much more stable oc. which slots for memory are u using? in cpu-z on the memory tab does it say dual or single? let me know, here's where I stand...

and stock....

 

[Gryphyn]

I messed with it some more last night. I was wrong above, I had tried 1.45v for 3.7 Ghz (unstable) and 1.425v for 3.6 Ghz (unstable). Last night I tried 1.45v for 3.6 Ghz, and it ran though a 1 hr check on OCCT just fine. The graphs it generates showed my power supply to be extremely stable, which was comforting. I ran prime95 on a blend test all night and it was running just fine this morning, so I left it on for today too. We'll see how that goes. Max temp was 38C.

I haven't messed with my HT bus yet, it is still at 2000 mhz, memory at 1600.

My memory is running in dual channel mode, unganged. I have it in the channel 1 slots, because the (OCZ Reaper) heatpipes are so tall they can't fit beneath the tuniq tower to get in channel 0. Later on I may try to see if I can rotate the heatpipes a bit to get them in there.

 

[jadawgis732]

Wow, congrats on that! what are your Vantage results? and what GPU are you running....must be a great system. Did you try unlocking the 4th core?

 

[Gryphyn]

Looks like 3.6 Ghz at 1.45v is my sweet spot. It was humming along just fine when I got home, 38C load temp. I tested 1.4375v just to see, but it crashed OCCT after 40 mins. Just for kicks I tried 3.7 again, with 1.475v, no good. Tried 1.5v and it ran OCCT for 1 hr, but then dumped on prime95 after about 2 hrs. So, I could probably get it stable with more voltage, but my load temps were hitting 40C, so I'm gonna let that go and stick with 3.6 Ghz.

Since I'm running Win Xp, I can't test it on Vantage yet, but I just installed the Win 7 RC1, so I'll mess with it over the weekend and post my score. Then maybe I'll tweak the memory and see what I can get to. 3dmark06 (free edition) results are something like 16100 if I remember correctly.

I'm running a Radeon 4890 that I just got. I wasted a bit of money for it, it cost about 30% more for about 10% more performance over a 4870, but it is supposed to overclock quite well, and I wanted to play with OCing my video card too at some point.

No go on the 4th core. The bios that my MB came with was...F3c I believe, which I think hadn't yet been tweaked by Gigabyte to disallow unlocking. But, it didn't work all the same. I've since flashed the Bios to F5(something) to fix a problem with the bios screen locking up if you're using a usb keyboard...which I was. Heheh. Made it hard to change cpu clocks.

In looking at what to do next, you might head over here: http://www.ocztechnologyforum.com/forum/showthread.php?t=55369

I found some good information about what works best when tweaking your bus speeds and memory timings, maybe it will help you find stability.

 

[jadawgis732]

thanks a ton man, by the way what cpu cooler are you using. was looking at the vendetta 2 in microcenter today, but dude said 51 load temp is no worries

 

[Gryphyn]

I'm using the Tuniq Tower 120. Got it a few years back to use on my overclocked Opteron 170, and love cooler are you using. was looking at the vendetta 2 in microcenter today, but dude said 51 load temp is no worries[/quotemsg]
it. It is extremely large though.

My processor was happily running prime 95 when I got home at 3.6 Ghz, so I figured a 24hr test meant it was stable. I tried playing Left4Dead though and it locked on me. Maybe my video card doesn't like everything being so stressed. I'll have to tinker with it more when I get a chance.

I've read some posts where people think the actual temps higher than what we're reading on this chip. I've read maybe by 6 degrees, and I've read maybe by 20 degrees. I don't know what to think, really. Coretemp seems throw up an exclamation point when I've been above 40C at all, and my temps stayed below that until I started pumping 1.5v into it, so I arbitrarily set 40C as my limit. I've read posts where people have been far above that though...so who knows.

 

[Apache14]

Iv gotten a 720 at 3.8Ghz (1.55v set at bios) and it never goes above 41'C with a Zalman CNPS9300-AT i got for £22 of ebay and with a 4870X2 in the case lol

 

[mesro]

(Near newbie here) Hey.
I have the same processor and the motherboard asus m4a78 pro. I have a question about the BIOS. I have raised my multiplier at 16 and i have it at 3,2, but i do not know what the right point to increase your voltages (lol). I see processor voltage, CPU/NB voltage (which i dont know the difference). And when i hit processor voltage it says minimum is 0.8000 and interval is 0,0125. Where can i see the current voltage of my processor? If someone could explain how it is working , i would be pleased.


Thanks in advance, Mesro

EDIT: I have run OCCT for 2h for 16x multiplier and came with no errors. I had 29 C idle and 45-47 full load .

 

[Apache14]

i had to rais voltage by one step in the biod at a 16.5-17x mulitplyer for a stable run

 

[Gryphyn]

Mesro, you don't want to raise the NB voltage, you want to raise the processor voltage.

Don't raise it until your system becomes unstable at a certain clock speed. Raise the voltage a tic, and then try again. If stable, good, if not, raise the voltage another tic. You can keep raising the clock speeds and then raising the voltage until stable until one of two things happens:

1) you hit 1.55 volts Vcore, since that is the limit
2) your temperatures are just too high

As you can read above, I hit that point at about 3.6 Ghz, 1.45v. Pushing the clock speed any higher meant I really had to turn up the voltage, that that pushed my temps above where I wanted to run.

 

[mesro]

Mesro, you don't want to raise the NB voltage, you want to raise the processor voltage.

Don't raise it until your system becomes unstable at a certain clock speed. Raise the voltage a tic, and then try again. If stable, good, if not, raise the voltage another tic. You can keep raising the clock speeds and then raising the voltage until stable until one of two things happens:

1) you hit 1.55 volts Vcore, since that is the limit
2) your temperatures are just too high

As you can read above, I hit that point at about 3.6 Ghz, 1.45v. Pushing the clock speed any higher meant I really had to turn up the voltage, that that pushed my temps above where I wanted to run.

Thank you really much gryphyn. One more question what is the limit for temperatures ? I have mine at 3,2 with 1,325, should i try increasing his clock?

 

[Apache14]

Just to give an idea of proformance increase for each speed step and the voltages i was able to acheive under cpu score in 3dmark vantage

3.5Ghz @ 1.450v score 8855 idal 21'c load 35'c
3.6Ghz @ 1.475v score 9198 idel 23'c load 37'c
3.7Ghz @ 1.500v score 9338 idel 25'c load 39'c
3.8Ghz @ 1.575v score 9604 idel 29'c load 42'c

as you can see the from these teats the sweet spot is at 3.6Ghz and 3.8Ghz but the 3.8Ghz voltages are on the tad high side the the load temp going over 40'c is a lil much compared to the other temps

one big q is 1.575 with a load temp of 40-42'c too much ???

 

[Gryphyn]

The question about temps is a tricky one, because In all my searching I haven't seen a consensus on what a good max temp is. A lot of older posts talk about the temperatures being off by as much as 6 or 10C, but that may have been fixed in a bios update.

The max temp listed by AMD is 73C, but that is much too high for every day operation. In my experience overclocking my old Opteron 170, 50C was a good stopping point, so I've just selected that for this chip as well. Then, to be safe (until I can confirm otherwise) I've assumed my temps are actually 10C higher than what they are reading, which means I try not to go over 40C right now.

So, mesro, I see no reason why you couldn't try to go a little higher. Just keep watch on your temperatures.

Apache, if it were me I don't think I would operate at 1.575 24/7...that's a little too much voltage to be comfortable for me, and I think it might break down your chip over time. If you can get 3.7Ghz or 3.75 Ghz stable and below 40C, I might go with that. Are you checking load temperatures using Prime95? That program has generated the highest temps for me.

 

[Apache14]

Are you checking load temperatures using Prime95? That program has generated the highest temps for me.

Yep i am and im now running 3.7Ghz at 1.49V and a max load demp or only 38-39'C

From past experences with these phenom and phenom II i always went with 7'C higher
1, in a 25'C room how can the CPU be at 20'C with air cooler (still giving room for a 1-3'C rise before i could get into the bios thats is still insane)

2, AMD higest temp is 73'C at 40'C at load is almost half this that is also a lil odd iv never seen a chip that operated at half its max themal temp i would say. 40'C means 47'C(still very cool tho )

 

[mesro]

Now for example i am trying to 3,3 and i finally passed the prime95 small ftt 15 min test with 1,4 volts. Temperature in max load was 42-44. I am planning to go no more than 3,5 and of course being under 50. Thanks for your replies.

Mesro

 

[Apache14]

I would keep below 47C if you can and at 3.5 no more than 1.475-1.500 V

 

[Apache14]

Also if you are on a stock cooler id upgrade to something like this

http://www.overclockers.co.uk/showproduct.php?prodid=HS-037-ZA&groupid=701&catid=57&subcat=1395

That can keep mine @ 3.8Ghz with a voltage of 1.575 under 46'C ALL THE TIME

 

[mesro]

Basically, now i have passed 2 h prime95 small fft at 1,425@3,4 ghz and max load at 43-45. That's nice. I will let the test continue till tomorrow so as to have 24 h passed. Then i ll try to go till 1,475-1,5 as you said and 3,5-3,6. I got this cooler http://www.plaisio.gr/product.aspx?product=1219820&Manufacturer=Scythe&category=69977719&catalog=20

Sorry for the site.

 

[Guest]

Tom's hardware said in their cooler 4 part special that cooler you linked is extremely inneficient (very poor cooling.)
Might explain your higher temps

 

[ltwo]

so would you guys say 45-50*c is an acceptable temperature for 3.6GHz on load?