Overclocking 955 BE

JonSmith

JonSmith

JonSmith

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Hey guys, I've currently been trying to push my 955BE to the limit, and I was wondering if there are any expert clockers who have some tips.

My specs are as follows:

Gigabyte MA770t-ud3
Phenom II 955 BE C3
4x2GB DDR3-1600 RAM 1.5v CAS9 @ 1333 CAS8
MSI 6850 power edition OC @ 915 core 1100 mem
500W OCZ PSU
Asus Axe square CPU-cooler (before you guys say anything, you can't argue with getting it for £12 courtesy of OCUK!)

Firstly I ran some tests at the following settings, with everything at stock and simply varied the CPU multiplier and volts. As a note my motherboard suffers from a bit of Vdroop as the actual voltage I read in windows is always 0.015V less than is set in the BIOS. I've been running the large set for error checking.

3.7GHz @ 1.33V - OCCT crash after 10s
3.7GHz @ 1.36V - OCCT crash after 2min
3.7GHz @ 1.39V - OCCT stable (20 minute test), crash in BF3 multiplayer and company of heroes multiplayer in 3h. Max temps 45C
3.7GHz @ 1.41V - OCCT stable (20 minute test) and no crashes, but I've had it running like this for months anyway. Max Temps 47C.

All tests performed with an ambient room temperature of 24C. HT freq at stock, NB at stock and all voltages except CPU at stock.

After this I added an extra 2 RAM sticks and tightened the timings on the RAM to CAS8 @ 1333. System stability was unaffected. Technically my RAM will run at 1600 but when I tried it blue screened once every 2 days on average, not tried it with 4 sticks. I've heard raising CPU-NB volts is supposed to help with this, all I was doing was raising the RAM multi to 8 to give 1600 as my motherboard supports it. Higher RAM volts did not help.

I've just ran another test for 3.9GHz @ 1.44V OCCT stable for 20 minutes, max temps of 52C. Will run some gaming tests later.

So from reading around the voltages required for my overclocks seem higher than the average. Any comments on this and the temps would be appreciated. My cooler is slightly better than my old freezer 7 pro for reference, when running the same clocks.

So to summarise, my questions are as follows

1) How do I get my RAM running at 1600 without crashing?
2) What additional overclocking tweaks could I perform for extra performance?
3) If anyone is using my motherboard model, did a BIOS update help with the overclocking?
 
Well first of all Hi, I have had a Phenom II 545, 955 & I am currently on a 960T unlocked to 6 core @4.1 with CPU-NB 2600 & RAM @ 1600

My 1st question, what brand and model of RAM is it? AMD systems and RAM = pita. You will need to make sure it's at 2T as a baseline. I would also suggest keeping it CAS9 for the mo. Tightening RAM latencies should be your last port of call.

Personally I and many many others prefer Prime95 blend test as a thorough test of CPU, RAM & NB.

Imo first off, run a 1 hour test on Prime95 with your current settings and see if it passes and what temps that throws up.

Overclocking by the multiplyer is the easiest way with BE chips but a combo of FSB and Multi will give you the best results.

Really I could write for an hour going into very boring detail..but luckily someone else has....ps click quick cos I can't rememeber if I am allowed to post these links :D

CPU oc'ing

CPU-NB & RAM Oc'ing
 
2x OCZ3P1600C9ELV2G and 2x KHX1600C9D3/2GX

The OCZ RAM is ELV RAM but I tested it at up to 1.65V. The Kingston RAM is supposed to be DDR3 1600 @ 1.65V but it actually runs at this speed with 1.5V. The issue doesn't appear to be the RAM itself but rather some configuration option on the motherboard, as it passed memtest but it would just intermittently crash every couple of days.

3.7 @ 1.41 volts was also tested as prime stable, the PC hasn't crashed in months since I reverted the RAM back to 1333. I use OCCT because it finds the errors quicker than prime when trying to rule out bad clocks quickly.

Do you think that raising the FSB clock will allow for a lower core voltage? As it stands heat is the main issue and anything I can do to lower the voltage will help that.

EDIT: Ran a stability test and did some gaming at 1.47V and 3.9GHz which it passed. It crashed at 1.44V. It was hitting 56C core temp under stress so I think this is the best overclock I am going to get with my current cooler. Not bad but It'd be nice if it didn't need such a high voltage.
 
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I will check out your RAM for you when I am about tomorrow.

Well that sounds ok. Voltage is a bit higher than I'd expect but then again it's hot and miss going over 3.7ish with these chips. If it was one of the first versions this is about normal.

I had your Mobo. If I were you I'd make sure I was getting plenty of cold air over those vrm's. They get a bit toasty.

Will you hit the same fsb OC at the same voltage..can't say really, depends on a lot.

I suggest trying 230 fsb with x16 multiplayer @ 1.44. You will have to bump your RAM and HT multiplyer (on phone, spelling can wait till tomorrow). Keep your HT as close to 2000 as poss and your RAM under 1333 but make sure the timing in ram is cl8. It might auto adjust it tighter but we want to take the RAM out of the equation. Will update and go into more detail when I am home. when I am home
 
Thanks for the help. Currently my CPU fan blows directly onto the CPU VRMs, drawing air through a 120mm side vent in my case. The main reason I swapped from the freezer 7 pro was to take advantage of that vent by using a vertically orientated cooler. I also have a rear mounted case fan that is drawing air from the VRM area. I'm quite glad I got that fan whilst they were so cheap as afterwards I read about overclocking on 4+1 phase VRMs and people stressed how important it is to keep them cool.

One thing that I think I might do to help with the cooling is add a front 80mm fan, since there is a lot of static warm air around the HDD/GPU area at the bottom of my case.

Also I did a little reading and there are a lot of people who say it is tricky to get DDR3 1600 speed using Deneb core chips without making compromises, so I might try to tighten the timings to 7-7-7-20 after I've checked everything else.
 
Far more important than your ram timings would be your CPU_nb

Now very important this bit...

Raise your CPU_nb to 2600 and your CPU_nb voltage to 1.2 and test...could take a bit more voltage than 1.2 but well that it what testing is for. Keep an eye in ur temps because the CPU_nb is in the CPU therefore mote more voltage = more heat.
 
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