How to break 3.8Ghz Phenom II 64-bit?

[Belmont]

I am about to go insane. I have a very stable psu (OCZ 1000w) and Mobo (M4A79 Deluxe) and if I go higher than 3.9Ghz my PC becomes super unstable. Currently while idle I get 38C and under a full load 40C@3.8Ghz.....I would like to know if there is any way I can push my cooling to the limits for my CPU, as I am already running 1.45vcore and just cant break 4Ghz no matter what I do. BTW I have also heard someone has gotten 4+ghz on a 64-bit OS w/ a Phenom II...

 

[Idontcare]

This is pretty common with AMD's Stars core, both 45nm and 65nm Phenoms seem to have 64bit stability issues when pushing the GHz. Something in the architecture needed a few more delay stages to allow the 64bit instructions to complete, latency is timed too aggressively as the clockspeed scales. All those 6GHz+ records were done on 32bit as well.

 

[PingviN]

My Phenom II 965 also hits the wall at 3.8-3.9. 3.8 is stable at stock voltage,but 3.9 requires a bump to 1.5v. Any higher than 3.9 = No boot/Bluescreen. With your temperatures I suppose you should be more than able to push the CPU voltage to just over 1.5v.

You can try and boost the NB speeds as this might be a bottleneck. Try overclock it to 2.4-2.6 (for me this means a 1.250v for CPU-NB). Lower the HTT to ~2000mhz and give the RAM another 0.1v.

 

[n7]

The solution is called Intel. :sneaky:

Seriously though...even AT's own articles here have basically outright said you ain't getting much over 4 GHz on Phenoms in x64.

 

[nyker96]

The solution is called Intel. :sneaky:

Seriously though...even AT's own articles here have basically outright said you ain't getting much over 4 GHz on Phenoms in x64.

that is funny. but I think you can also get the C3 revision that supposedly allows a 100-200Mhz more headroom meaning 4 is reachable now at a reasonable voltage for AMD K10.5s. actually xbit has a review of it up this morning. looks like the usual revision improvements lower tdp, higher oc. check it out.

 

[SlowSpyder]

I've read about plenty of 4GHz+ PhII's, but I don't think that's the norm for these chips. The newer models seem to OC a bit better than the older ones, but my guess is you're about as high as you're going to get without insane voltage. My 940 gets shaky above 3.7GHz no matter what voltage I've tried (I've ventured above 1.5 for testing). Good luck, but even at 3.8GHz I would think it'd be a pretty quick chip, though obviously not going to pass up any i7's.

Now that winter is coming, maybe I'll try some more. I live in a cape cod style home that is older, the upper room is where my PC is. In the winter it'll be 60F in that room, maybe less, perhaps I can finally break that 3.7GHz mark.

 

[formulav8]

The new C3 stepping has allowed some reviewers pass the 4ghz in Vista 64 Bit.

http://www.pureoverclock.com/article845.html

That link above has someone getting over 4100mhz using a 64Bit os.



Jason

 

[BD231]

I'm running @ 3.73ghz with an x3 720 and can't get much past this mark in 64 or 32 bit. C3 stepping might be helpful but there's no real indication it's a sure thing as of yet.

The best thing to do with these chips is test for max stable overclock and leave them be, otherwise, you'll be posting on message boards about how you're stuck where everyone else is.

 

[PingviN]

It wasn't stable enough for benchmarking/stress testing, but it got me a validation

 

[richierich1212]

Belmont what processor do you have?

 

[lopri]

Looks like the new C3 stepping fixed the 64-bit bug.

http://hothardware.com/Articles/AMD-Launches-125W-Phenom-II-X4-965-CPU/

But for all intents and purposes, it's best to max out the frequency of these CPUs at default voltages than gaining 200 MHz at the cost of extra voltages. For better performance, I'd suggest you toy around the NB frequencies.

 

[Idontcare]

Looks like the new C3 stepping fixed the 64-bit bug.

Is it really fair to call it a bug?

Its really just a manifestation of the fact that the 64bit instructions have less engineering margin at any given Vcc, temperature, and clockspeed for stability in comparison to the engineering margins of their 32bit versions at the same Vcc, temp, and clockspeed.

It would be a bug if it turned out that the engineers had actually intended to engineer the 64bit ISA to have the same engineering margin as the 32bit ISA.

Regardless we can't really claim the issue has been put to rest as we don't have any overclocking results of the new C3 chip comparing peak overclocks on 32bit versus 64bit.

If the new stepping merely elevates the headroom for both but fails to close the gap itself, then the gap between peak clockspeed in 32bit OS versus 64bit OS will still be very much a real experience the consumer will continue to endure.

 

[Belmont]

Well, I am glad I am not the only person... Now here is my new question - how high can I bump the Vcore on my Phenom II before the actual chip gets damaged? Is it limited by heat or by material?

 

[Idontcare]

Ben90, do you have that post link handy regarding voltage and damage? I'm searching but I've haven't mastered this search engine yet.

 

[kalrith]

I'm sure a hammer would do it.

 

[Smoove910]

Why not roll with 3.8ghz and run tighter timings on your ram? I would think this would give you the best of both worlds....

Just my .02

 

[Belmont]

3.8 Ghz is not enough...Mainly because I play EQ2 and it seems to be limited by my processor, yet at this clock I still lagg, but if I underclock my 5870s all the way my FPS doesn't budge. So I know its the CPU - I am also thining it is my mobo, since I built this computer right when the 955 came out I ordered the M4A79 Deluxe mobo (DDR2) so If I switched to the new Crosshair III or the newest M4 w/ DDR3 would that change anything?

 

[lopri]

If 3.8 GHz Deneb isn't enough for your gaming I can't think of anything that'd help you. Are you sure there isn't something else wrong with your setup? How do synthetic benches score?

 

[Idontcare]

3.8 Ghz is not enough...Mainly because I play EQ2 and it seems to be limited by my processor, yet at this clock I still lagg, but if I underclock my 5870s all the way my FPS doesn't budge. So I know its the CPU - I am also thining it is my mobo, since I built this computer right when the 955 came out I ordered the M4A79 Deluxe mobo (DDR2) so If I switched to the new Crosshair III or the newest M4 w/ DDR3 would that change anything?

What does task manager look like when you are playing the game? Are any of your cores pegging at 100% utilization?

 

[Belmont]

To answer your question about core usage...one core sticks at 90-100% and one more hits around 30% and the others are around 1-5%. My Task manager also shows the only cpu usage is ofr EQ2 and it takes 2.2gigs of memory.

Also for synthetic benchmarks...I need to get one. the only bench I have ran is the crysis one with every setting maxed and got 47 avg fps on the default lvl - yet it doesn't even get close to maxing the usage of anything. On HAWX with everything maxed I get 117 avg and 370 max on its benchmark. I am pretty sure there is nothing wrong with my setup... I built it myself and every time I have installed a new piece of hardware I have done a clean windows install.

I will also mess with my RAM settings when I get home...The timings could be wrong since I flashed my BIOS.

 

[Idontcare]

Thanks Belmont, that pretty much confirms it then in my book. Interesting to see such a "cpu bound" game, and by the looks of it the game is almost single-thread bound sound thuban/gulftown aren't going to be much help either. You need more GHz, not more cores.

 

[faxon]

3.8 Ghz is not enough...Mainly because I play EQ2 and it seems to be limited by my processor, yet at this clock I still lagg, but if I underclock my 5870s all the way my FPS doesn't budge. So I know its the CPU - I am also thining it is my mobo, since I built this computer right when the 955 came out I ordered the M4A79 Deluxe mobo (DDR2) so If I switched to the new Crosshair III or the newest M4 w/ DDR3 would that change anything?

dude you are gonna be better off just dual boxing that shit than trying to get a bit more out of it. i run 2 copies of eq2 on my rig without any change in overall performance, but guess what, no amount of overclocking will make the game perform the way normal games do, in its current state at least. not until SOE updates the engine will this problem go away, and that would require moving the entire combat mechanics engine and most of the rendering to the GPU where it belongs, instead of doing so much of it on the CPU like it has been since launch lol

ed: here's a pic of my rig's task manager running 2 copies of EQ2, ACT (advanced combat tracker, its a log parser), ventrilo, and firefox. while for most games this may seem insane, for me its just another day of dual boxing. my results would be approximately half that if i were running a single instance of the game, with one core completely idle and another at 10-15% with firefox vent and ACT on it, unless im parsing a big log all at once, in which case it maxes out until its done sorting through the data (hundreds of millions of lines of logs). i should add that the loads on the not fully loaded cores go up while im in combat lol. this was taken idle in the Wanderer's of Norrath guildhall on nektulos server, in our qeynos side guild hall. video card is running at idle temps

 

[richierich1212]

Talk about inefficient software.

 

[Makaveli]

What are you using for cooling??

Your chip only goes up 2c at full load from idle?

 

[Belmont]

I am running a high flow system in a single loop with a triple rad that has 3 high CFM fans and shrouds w/gaskets. My lines are .5" - using 15% antifreeze and 85% distilled water with an enzotech WB lapped of course w/ artic silver thermal compound.