Help me overclock my opty 170

Hi all,

I wonder if some of you could help me overclock my new cpu. I was posting in the official opty 170 overclocking thread but my noob questions were getting in the way of the big guns

Ok here, it goes:

I have tried 210 x 10 = 2100, this works fine
Then I tried 215 x 10 = 2150, this also works fine

Then there is a brick wall at 216 x 10

I have tried everything that I know in order to get past it (but I dont know all that much )

1)Increasing the voltage to 1.375 (the next option in the bios) results in the machine failing to boot, when it gets to the xp loading screen it just restarts, this continues on a loop.

2)Lowering the LDT multiplier from 5x to 4x causes the machine to post and pass the windows loading screen normally, but then instead of the logon screen its just a black screen with the windows cursor on it.

3) Lowering the multiplier and raising the FSB 240 x 9 the system posts and then when the windows xp boot screen is about to appear, it restarts, this continues on a loop until stopped.

The stepping is:
OSA170DAA6CD
CCBWE 0551UPMW
1392568L50&&3

Memory is at ddr400 - This is equivalent to 1:1 right? AGP is fixed at 66mhz.

My specs are in my sig, im running bios version 26 and have downloaded and installed the amd dual core driver from the amd site. let me know if theres any other info I can give you.

Can anyone suggest what is causing my severe lack of overclocklability or suggest how to improve it?

Cheers

Stab in the dark here but is there a later BIOS which might better support the chip?

It's odd for an Opteron to max out at such a low level. You've tried what I'd recommend to

Yep, setting the ram to DDR400 sets it 1:1. You could try a divider just in case

EDIT: Just seen your edit and checked the site - BIOS 26 is the latest one. Have you had a chance to see if the board clocked at all with a different chip?

Hi, thanks for the reply,

The bios is the latest version, I updated to this version when installing the opty as its the only version of the bios that supports the amd dual core range (and even then theres no mention of optys just x2's) There were problems detecting it properly before the bios update, I didnt try any overclocking, just sorted out the detection issue first.

On older bios versions my 3500 newcastle reached 2.5 once, but It wasnt stable, I didnt really do much overclocking then, so I dont have any cast iron figures, but I bought the 170 thinking I could overclock it to the hills.

I suppose theres one thing I havnt tried, thats overclocking the opteron whilst on older bios (when detected as an AMD hamer family cpu - model unknown) although this bios clearly offers even less support than my current version.

Apart from that is the solution to buy a new board, new ram or what? I cant afford a new mobo right now because I am still on agp graphics, and I would have to fork out for both new mobo and a new gfx card

Cheers

If you have an option in bios to select ddr333 use this and you should be able to push up the fsb (htt) much further without problem. It sounds to me like your memory has reached its limit at 216mhz. Leave the ldt multi at 4x. Give it a try and post back the results.

Hi

I really don't know - I'm rather stumped. To get the Newcastle to 2.5 you'd need an HTT of at least 227MHz (11x227 = 2497MHz). Your Opteron isn't managing this and it should be a far better clocker

Do you know someone with a Socket 939 motherboard that'd let you test your CPU in?

As for a new board, you can get nice AGP boards like the EPox NForce 3 Ultra based board. I'd also look at the ASRock Dual board as it has native PCI-E and AGP slots

Hi IzaLearnin, Im just testing out that idea on the desktop now, running the memory at ddr333. Will report the results back as soon as Im done.

To ajgoodfellow again, I do have another 939 board in the family machine in the other room, The problem is though I built it for everyone to use for office applications, so it has the power of a mars bar, meaning I would have to take my gaming rig, and that machine, de-assemble the major part of them both and make a new, 3rd machine from them, It will take a while and isnt something I particularly want to do, but if IzaLearnin's suggestion doesnt work then I will have to do exactly this.

Ok here goes, Dropping the DRam clock to DDR 333 has enabled me to sucessfully boot at a higher fsb (htt)

Everything seems fine at 235 x 10 = 2351Mhz with the ldt multi at 5 x although I have not put the machine under any great stress or tested at great length. Temps are 46 - 48C Idle

I went up to 240 x 10 = 2400Mhz with the ldt at 5 x but it blue screened after a couple of minutes of use. Seemed to be a memory error as it showed a couple of numeric memory addresses but wasnt on long enough to read.

What do you think I should do next? I was thinking trying the 240 x 10 with the ldt dropped to 4x.

It must have been your ram then!

Definitely drop the LDT multiplier to 4x, perhaps even 3x

As a rule of thumb you don't really want your HT speed to go over 1GHz - at the moment you've got it stable at 1175MHz! (5x235).

I'd set it to 4x for HTT speeds of up to 250MHz, 3x for HT speeds of up to 333MHz, etc

Ldt bus needs to be kept to around 1000. It is arrived at by the formula ldt multi x htt frequency so with a htt of 240 the ldt multi needs to be 4x giving 960 in total. If you manage to push up the htt above 250 drop the multi to 3x. Using the ddr333 memory divider your ram speed is htt240/6x5=200mhz which means it is running at ddr400. You need to keep it under 215mhz (ddr430).

If you still have problems with stability with a htt of 240 increase the cpu voltage by 0.025v and try again.

Am on call this week so I am away to my bed neeed....sleeeeeeeee

Ok my thanks to you both, you have been very helpful.

Its now stable at 2401Mhz
Thats with 10 x 240 and the LDT dropped to 4x FSB, so far so good, I ran 3dmark03 (seeing as it had previously crashed at this speed with 5xfsb) just to make sure and it all ran fine, put 400 points on my previous best too

I am off tomorrow so I will come back and try to push it further in the morning some time, the higher it goes though, the more stability testing its going to need. Ideally I want to get it over 2.6Ghz, but we will see what happens. (I have promised myself watercooling if I can get it that high

Cheers

Glad you got it clocking in the end!

I was a little doubtful at first!

Ok, we're off again

Running at 2420mhz.........242 x 10 with the ldt multiplier set at 4 x, the ram is still at ddr333 and the voltages are all stock. This works fine.

Raising to 2430mhz.........243 x 10 with all the other settings kept the same, is unstable.

Threfore I raised the voltage up by 0.025v. And it was still unstable.

What do I do now? Do I raise the voltage again, or what.

Cheers

You could try a lower divider, just in case (with the HTT at 243, at the ram set to DDR333 your ram speed will be 243x(166/200) = 202MHz which should be fine)

Perhaps try raising the CPU voltage a little further - try 1.4V

You need to check your memory timings.
Many mainboards will select lower timings if you use the 333/266 divider, once overclocked the memory operates above these speeds and the timings are to tight for reliability.

Use CPU-Z (small download) to view you current memory settings. You can then change these in the BIOS.

If you post your current settings you'll get more specific advice

AD

Ok, CPU-Z screenies:

Here

and here

Hi mate, just in from work-bummer! What voltage is your ram set to in bios? It may just need a 0.1volt increase to stabilize it at higher speeds without changing the timings. Which of the Geil ram sets is it? Will be out for a while but will check back.

Hi again mate.

The ram is at 2.65v and it is the BH Set that I am using.

Edit:

Hi ajgoodfellow

I have been playing with your suggestion for the last 15 - 20 mins, and all seems good, thats with the cpu core now at 1.4v

Edit again - This isnt stable afterall so its off to ram voltages for a solution I think.

Thats exellent ram but needs high voltage and a fan directed at the sticks to get the best from it. Can your m/board supply enough voltage (3.4v-3.5v) to the ram slots to run at ddr500 with 2-2-2-5 timings? If not I would leave the ddr333 divider in place and try 2.8v-2.9v for the ram at 2-2-2-5 timings and continue to raise the htt 5mhz at a time and test with a 1mb superpi run each time until you encounter instability again. I am sure 2.6ghz is acheivable with your 170 as long as you can keep it cool.

With regards to cpu temps google for "max tcase" a small application that tells you the max temp you should allow on the cpu. With my Opty it is 61c so to be safe I don't run it any higher than 51c under load except for benchmarking.

The bios is only offering options up to and including 2.8v for the ram. The DRam clock can be set to ddr500, but I am guessing that without the ability to provide it with the 3.4v -3.5v that you mentioned it will not run at this?

IzaLearnin said:

If not I would leave the ddr333 divider in place and try 2.8v-2.9v for the ram at 2-2-2-5 timings and continue to raise the htt 5mhz at a time and test with a 1mb superpi run each time until you encounter instability again. I am sure 2.6ghz is acheivable with your 170 as long as you can keep it cool.

Click to expand...

I'll get going on that then.

Cheers