Newbie OC help - i7 - 920?

[Otis11]

So i'm a newbie when it comes to OCing, but decided I wanted to try. As far as I can tell I have this stable with the specs below, but I'm trying to pass 4Ghz and can't seem to break it. I've tried 191x21 and 200x20, but both crash between 1-5 minutes after boot. I know 200 Blck works because I tried 200x18 and it ran fine. (Then again I only ran it for about 30-35 minutes on Prime95, but it never crashed.)

Any suggestions?




Note: Max temp is at 76 for now running WCG full bore. That's well in the safe range for 24/7 right? Just double checking. Thanks for the help!

[DAK1640]

Loosen your mem timings and add Vcore...What Ram are you using?
tRFC looks mighty low.
tRAS looks a little low also

[artemm]

Disclaimer: I'm a newbie too.

However, from what I've seen, that temp is kinda high for a D0.

What cooling are you using?

I just recently started tinkering with my 920 too, but only got to the 3.9 mark before I had to leave on my trip. It'll be getting its trial by fire via 1 month of BOINC with no supervision...

Btw, check that windows/BIOS is detecting all of your RAM. I think I screwed up my socket because BIOS and Win only detect 4Gb, while CPUz detects 6...

[Snow Crash]

Along Dak's line of thought ... what are stock ratings on your memory?
What do you have vDIMM set to ?
What do you have VTT set at?
What mobo?

[Otis11]

Mobo is P6T (not Deluxe) - CPU is D0
Cooling is a Scythe Mugen 2 (reluctant to raise vCore because of temps... Pretty sure I'm over the necessary voltage for current clock though)

How do I change tRFC and tRAS?
vDIMM and VTT are on auto. Not sure what that comes in at...?
As for the ram its 1600Mhz at 1.65V (read from the sticker)

Just a note: this is all for WCG performance so I'm not really worried about the RAM speeds if they don't affect other things. Nothing else that I do is that demanding...

Another edit: I just looked in BIOS to find VTT and vDIMM and couldn't find what those were referring to. I know what they are, just so many options... And kinda afraid to start flipping numbers when I'm not sure what they do...

[Jaco]

Otis,

The uncore multi could be giving you issues . It's at 16x , while your dram multiplier is at 6x. (uncore should be 2x dram speed)
I'd change your dram multiplier to 8x. Better set vdimm manually to 1.64-1.65v

[Jaco]

Another note : don't leave voltage settings on 'AUTO' with Asus boards.
'AUTO' might give you way higher than default voltage.

[v0dka]

VTT is called uncore voltage on Asus boards, iirc.

76C is not unsafe but too high for an increase in clocks. You should get a strong room fan, point it at the open case and put the whole thing in front of an open window to eliminate the heat problem. See if that does it.

That should even allow for some added voltage. Try the VTT voltage as well as Vcore. Some cpu's need added VTT for increased core clocks but this Xeon I have hates it so just try and see what happens. You might even have to put the VTT at a very specific value because one step more or less is unstable. I wouldn't go above 1.4v VTT though with these temps.

Also yse the odd multipliers, i.e. 19 and 21 they are often more stable.

[Jaco]

I think it's called 'QPI/DRAM' voltage in Assus talk

[Snow Crash]

I have one of these boards. I am currently running WCG and Einstein 24/7 @21*203 ...

If your RAM has an XMP profile use that first to get appropriate timings/ subtimings.

Now go back and change the cpu settings and voltages.

vCore = 1.3625
vQPI (VTT) = 1.3875
vDIMM = 1.66
Pick the mem multi (closest to 1600)
IIRC the other multiplier settings fall into place, just pick lowest setting available.

You really can't go much above this vCore and raw GHz as the bios on this board does not allow you to bypass v throttling. Even at these settings if you open RealTemp and then launch Linx you will see the multi in the top right of RealTemp drop almost as soon as Linx hits 100% CPOU utilization. Running Prime/ WCG (pretty much any DC app) stay just below the throttle and has been very stable for me. I am using Megahalems with temps in high 60s to low 70s.

[CaptMorgan]

Water-cooling is preferred for anything above 4?

[Snow Crash]

I am running rock solid on nothing but air. Granted my case is a HAF932 which has great flow and a Megahalems with temps around 65-72.

My second rig is an EVGA SLI LE with a C0 chip. I can just barely run 4 GHz (well 3990 but who's counting) which is a limitation of the chip itself, no more scaling with more vCore I have this running caseless with a Xigmatek 1283 DK (21*190) vCore 1.4125, VTT 1.3875 and temps are a little on the warm side at 72-77 but still quite safe.

While I have switched the chips between mobos, goofed around benching, flipped GPUs, turn them off for vacuuming, I have had very little downtime. The C0 has been running 24/7 for the better part of 10 months (except for 2 months mid summer when I tuned it down to 3.2) and the D0 for about three months. No signs of degradation on either chip and no problems so far with the mobos.

[Kingcarcas]

Wow, i would never run my cpu above 65, good luck you have some balls good sir!

[Otis11]

I have one of these boards. I am currently running WCG and Einstein 24/7 @21*203 ...

If your RAM has an XMP profile use that first to get appropriate timings/ subtimings.

Now go back and change the cpu settings and voltages.

vCore = 1.3625
vQPI (VTT) = 1.3875
vDIMM = 1.66
Pick the mem multi (closest to 1600)
IIRC the other multiplier settings fall into place, just pick lowest setting available.

vCore @ 1.3 cuz I'm as hot as I'm willing currently. Maybe once I can sit and watch it for a few hours I'll bump it up

As far as the other voltages, I have CPU PLL Voltage, QPI/DRAM core Voltage, IOH Voltage, IOH PCIE Voltage, and DRAM Bus Voltage... (I also have a DRAM DATA REF Voltage and a DRAM CTRL REF Voltage on each stick of RAM if that matters?) - All of these are on AUTO, what should they be on?

Also, for the mem muli it doesn't show the multiplier, but I'd guess the 8x is at 1491? The only other choices are 1119 or 1864...

Thanks for all the help guys!

[Snow Crash]

OK ... I think your issue is the QPI/DRAM (this is VTT) if you have left it on auto it is sitting at stock which is 1.2 and likely much too low for 6 GB RAM, even at 1491. Yes, I have not looked at the BIOS in so long I forgot that is just gives a speed and not the actual multiplier. Other than the DRAM Bus (set to 1.66) I actually set all of the others' to default values (the data refs I left on auto).
Does your RAM have an XMP profile you can load to get the subtimings? If not I would suggest bumping the tRFC up a fair amount maybe to low 70s. It's not like your RAM timings are going to effect WCG runtimes, you just need something that will work. Once that is done you really should only need to mess with vCore and QPI/DRAM. I would start again at stock volts (vCore 1.2 and QPI/DRAM 1.2) and work your way back up in small steps to see where you are stable. I use one pass of Linx at full RAM and SPi 4 M to start to find when I need to bump volts.
Once you get close to your 1.3 vCore max (are you sure you have a good mount, those temps seem a little high for 1.3?) then you will need to expand your stress testing. I go with 5 passes Linx max mem, 1 pass sPi 32M and finally 2 hours Prime95 Blend. I have never had a WCG error if I have passed these tests.

Wow, i would never run my cpu above 65, good luck you have some balls good sir!

The i7s just run hot. Balls, no ... by spec they don't thermal throttle until 100C so I am sure they can take low 70s easy, heck I bet going into the 80s 24/7 would be fine but my chips just don't scale much over where I am now so I have no need to run at volts that would take my temps that high. I will be replacing with hexcores when they are available so I'm not to worried about a $200 chip.

[my87csx481]

Otis,

The uncore multi could be giving you issues . It's at 16x , while your dram multiplier is at 6x. (uncore should be 2x dram speed)
I'd change your dram multiplier to 8x. Better set vdimm manually to 1.64-1.65v

Are there any other "rules" like the bolded one above that should be followed?

I may, finally, be able to get a socket 1366 in another month so, I'm interested in everyone's advice as well. Unfortunately, I have not had the free time to read and keep up with everything for at least a year....so I know next to nothing about 'em.

[Snow Crash]

difference between VTT and vDIMM must be no higher than .5v
i7-920s like odd CPU multi (not a rule but an observation, certainly was true for the C0s.

[Otis11]

Just wanted to say thanks for all the help guys. I'm still tinkering with it, but as I'm currently moving things back to college I don't have much time. I'll make more adjustments when I get settled down again.

[my87csx481]

Thanks Snow Crash.

Otis11: Sorry for sorta' hi-jacking your thread.

[Snow Crash]

It wouldn't be XS if there was no threadjacking

[Otis11]

Thanks Snow Crash.

Otis11: Sorry for sorta' hi-jacking your thread.

Na, don't worry about it.

With how little I know, if it helps you, it's definitely going to help me.

[Otis11]

Ok, epic thread revival.

So i had to drop it down to 3.5 as it became unstable after I moved back to college, and am just now getting a chance to play with it. So here's what I have:

Ai Overclock tuner [X.M.P]
-eXtreme MemoryProfile [Profile #1]
-Profile Info: 1600MHz-8-8-8-24-2N-1.65v-1.35v (this is just a label)

CPU Ratio Setting [Auto]
SpeedStep Tech [Enabled]
Turbo Mode Tech [Enabled]
BCLK Frequency [185] (sure this can go higher, just getting everything else set first)
PCIE Frequency [100]
DRAM Frequency [DDR3-1483MHz] (Will bump this after everything else settles)
UCLK Frequency [Auto]
QPI Link Data Rate [Auto]

CPU Voltage [1.33125] (need to re-seat before pushing this)
CPU PLL Voltage [Auto]
QPI/DRAM Core Voltage [1.33125]
IOH Voltage [Auto]
IOH PCIE Voltage [Auto]
ICH Voltage [Auto]
ICH PCIE Voltage [Auto]
DRAM Bus Voltage [1.60] (XMP set this to 1.66V, but is that ok?!?!)
All other DRAM on Auto

And now to see if this is stable... Any suggestions?

[my87csx481]

Another note : don't leave voltage settings on 'AUTO' with Asus boards.
'AUTO' might give you way higher than default voltage.

Take this advice seriously.

The few Asus boards I've had all overvolted when left at AUTO while manually increasing frequencies (Vcore, NB, SB, RAM, possibly VTT). I usually set voltages to whatever the stock value is that AUTO sets (with everything at stock/fail safe), and then increase voltages as needed when increasing frequencies.

Be careful man.

[artemm]

P6T series motherboards are weird in that they can't set 1.65 volts. You can set 1.64 or 1.66, so the board rounds up the XMP profile, lol. Set it to 1.64, you'll be fine.

As others have said, never overclock on those boards without setting all voltages yourself. Select each voltage individually and set it to the default setting (the board itself will tell you what that is on the right-hand side, or you can look it up.)

Turn ALL CPU functions OFF (except HT, of course.) Just go into CPU config and disable everything you can. Disable CPU spread spectrum and PCI-E spread spectrum. Disable all of the onboard junk you don't need.

Turn Load Line Calibration on, but watch it doesn't overvolt vcore.

Then you'll want to tweak the CPU core voltage, QPI-DRAM voltage, and maybe the IOH voltage by a few steps.

Start with CPU core at 1.3v and work your way up. I find that on these boards you'll need a QPI-DRAM voltage of 1.30v for 1333mhz RAM and 1.35 for 1600mhz. However, you'll probably want to underclock memory while you're finding your max CPU freq.

Keep uncore as low as possible (x2 DRAM.) Same goes for QPI.

Make sure memory timings are 8-8-8-24 (CAS-tRCD-tRP-tRAS). Also, the board will probably set this itself, but check that tRFC is set to 88. I'm assuming your memory's CAS 8, btw.

You should hit 4ghz with no more than ~1.365v on the CPU or temps over 70C. If not, there's something wrong.

One more thing to mention: in most situations, all Asus board I've recently tried undervolt. However, if you have LLC on, the vdroop is reduced and may actually turn into overvolting under load. Since I know you probably won't take a multimeter to your board, try using the bundled software to at least get an idea of what voltages are really set. Take it with a grain of salt, though.

/massive post.

Good luck!

[Otis11]

As it's running fine now, I don't see a problem with auto volts, but I'll trust you guys!

You should hit 4ghz with no more than ~1.365v on the CPU or temps over 70C. If not, there's something wrong.

And I'm sitting at 74C... Think I need to re-seat the HS. Unfortunately all the thermal paste is at home.

One more thing to mention: in most situations, all Asus board I've recently tried undervolt. However, if you have LLC on, the vdroop is reduced and may actually turn into overvolting under load. Since I know you probably won't take a multimeter to your board, try using the bundled software to at least get an idea of what voltages are really set. Take it with a grain of salt, though.

/massive post.

Good luck!

And I got two right beside me... Show me where and give me a reason why...