Overclock XP3000 'Venice'

[eletero]

Hi all,

I've recently purchased a new machine with the A-bit fatal1ty AN8 MB and the new socket 939 AMD64 XP3000 venice core.

I read the review [ http://www.hexus.net/content/reviews...lld19JRD0xMjU1 ] of the overclocking actually after I made the purchase. When I bought my machine I wasn't planning to do much overclocking, the main objective was silence - with perhaps mild overclock.

Anyway, after reading the article it started to wet my appetite so I thought I'd give it a bash.
The other components in my system are (I know I should have better RAM - but like I say I didn't intend to overclock to much before I bought the system)

Tagan 420W power supply
1Gb (2 x 512 Mb) Corsair Value Select Kit, DDR, PC3200, non ECC
Asaka evo33 (913) CPU cooler.

I followed the steps in the review, I dropped my RAM to DDR266, increased the nForce4 voltage to 1.65 and then started increasing the FSB in 5MHz increments.
I managed to get as far as 245MHz - a fairly mild overclock in comparison to the 310MHz acheived in the article. Anyway I played around a bit more and set all the RAM timings by hand (not auto) to the default settings and tried again.
Now I have the FSB running at 267MHz, which means the processor is running at 2403Mhz (a 600 Mhz overclock) and the RAM is running at 171Mhz.
I can't seem to get beyond that - I don't think it's the processor restricting me it's still running at 36 degrees idle with the evo33 running at slowest RPM (2400). I tried increasing the cpu voltage to 1.45 but no joy. I also changed the ram from 1T to 2T, but still no joy.

I would like to know what it is that's keeping me at 267FSB. I have a feeling it might be the RAM, but it might also be power? What do you think?

For the time being I'm happy with my overclock - especially with such low temperature and noise - I'm just curious to know what's holding it back.

Other question is, will running the RAM at 171MHz(DDR332) affect performance signifcantly? I can overclock the FSB to 216 without changing anything else, which means the CPU runs at 1944Mhz and the RAM at 216MHz (DDR432)

What's better,
2.4Ghz DDR332
1.94GHz DDR432

Thanks

-e

[Rave]

2.4GHz with DDR332 will be much quicker. However, you could try setting the RAM to DDR333 in the bios which will bring it up to speed (maybe you'll have to back off the CPU speed by a few MHz).

As for what's limiting you- did you set the Hypertransport multiplier to 4x or 3x?

[eletero]

Hi Rave,

I did try setting the RAM to DDR333 but stability dropped significantly - dunno why. I couldn't even get beyond 225FSB with DDR333.

Sorry, should have said, the Hypertransport multiplier is at 3x.

I need to get a better benchmark, but I ran the prime95 benchmark and
the first FFT operation dropped from 22.8 to 18.3 seconds when going from,
216FSB 400DDR to 267FSB 332DDR. So it does seem much faster.

The corsair value ram timings are bad 3 - 4 - 4 - 8, but people say it overclocks to 440DDR. Would the RAMs stability be affected when running at lower than default speeds? Would relaxing the timings even more help?

Cheers
-e

[StormPC]

Your RAM is holding you back. It may do 440 MHz but at what voltage and for how long? Many A64's have quirky BIOS's. Some do not overclock well. Some are missing features that others have. Some are more (or less) stable.

When you ask which is better (2.4Ghz DDR332 or 1.94GHz DDR432) that all depends on your goal. If you live for synthetic memory bandwidth benches then 1.94GHz DDR432 will score higher. Most realworld applications and games will like the 2.4GHz more because Athlon 64's scale very well with an increase in MHz, due in large part to the on-die memory controllers.

If you want the fastest 24/7 stable overclock you should test at a fairly high ambient temperture. If your BIOS is working properly you want to run your memory at default timings (not auto...manually put them in), a 2T command rate, 166MHz divider, LDT x3 max, cpu volts about 1.53 max, DDR volts around 2.85 max, and leave chipset volts at 1.5.

With your CPU multiplier at max, raise your FSB in 5 MHz increments and keep rebooting into the BIOS until it won't post anymore. Then reset the BIOS to the highest FSB it did post at and test for stability. Many like to use Prime95 to test for stability, but I find that 3DMark2001 is a much more realistic overall system test. I've seen systems that can crunch all day long that are not at all stable for gaming. If you turn off the screens between tests on 2k1 it works the entire computer pretty hard.

Your goal (especially with your memory) should not be the highest HTT possible. If it is you should get some memory that uses Samsung TCCD chips. Running a high HTT only helps if you run super high quality low latency memory at high speeds. I think it makes more sense to go for the highest stable 24/7 overclock to get the most out of your system.

Play with different BIOS versions or ask around (or look around) to see what versions others are using. The BIOS can make a huge difference in the board's ability to overclock because there are many settings in a BIOS that are not necessarily adjustable by the user. Good luck and have fun with it.

[eletero]

After reading around a bit and looking again at why my overclock was limited to 265, I've realised my mistake.

I didn't flash the bios that came with my board (Fatal1ty AN8) - which I'm assuming is v 1.0. Of course support for the AMD E revisions (venice) didn't appear until v1.3. I've noticed that in the hexus article on overclocking they used version 1.3 of the bios. I've downloaded the latest bios (1.5) and will flash it tonight and retry the overclock. I'll report back tomorrow indicating what performace increase I get if any

Just thought I'd post in case someone was silly enough to make the same mistake.

Cheers

-e

[BUFF]

I've downloaded the latest bios (1.5) and will flash it tonight and retry the overclock. I'll report back tomorrow indicating what performace increase I get if any

Don't get your hopes up - most people think that 1.5 is flaky.

[eletero]

Do you think it's more advisable to get 1.3 instead then?

Don't suppose you know which bios ID letters correspond to which bios versions. The list at abit doesn't seem to include the an8

http://www.abit-usa.com/faq/mb/checkbios.php


Cheers

[BUFF]

According to FlashMenu 1.3 is BIOS Version NF-CK804-6A61FA1BC-13 - its the last 2 digits.

Of course all the BIN files start AN8 e.g. AN8_13

13 was first with Rev E support.

[sawyen]

StormPC is probably right, 24/7 stability is more important than your system's ceiling limit... The 3000+ and 3500+ i tested breached 9x295MHz HTT no prob for 15 hours on prime.. but I believe all OC comes at a price... I'm now running 2.6Ghz on my 3500+ at 37C idle rather than my CPU cum mobo limit at 2.83Ghz...

Your RAM could be a possible cause... That said, you could also bring ur NB voltage up by a little.. then pump some voltage to ur memory.. maybe 2.8V? CPU voltage for tiny vennies don't ever need to break 1.6V on modest 800Mhz OC... I believe you could probably breach 280 or maybe 290 (2.6Ghz)... but at what cost?... value rams don't handle extra voltage very well... It'll probably cook the memory controller in ur 3000+ plus a few capasitors in your NF4.. 265Mhz is already a healthy overclock... if you're planning to go anywhere further... invest in an extra 150 quids and get a TwinX Pro...