What is limiting my overclock?

[Ned_Flanders]

Yep, I'm back once again. From testing inviduatal components, I have found that:

1. My RAM, rated 2-3-2-5@DDR400 can do DDR520 at the same timings with 2.7V
2. My chipset will provide stable FSB's of 300Mhz+
3. My CPU can do 2.45Ghz stable.

I can get my 2.45Ghz from 288FSB * 8 on a RAM divider.

<b>So why can't I boot @ 2.3Ghz (1:1 FSB / RAM)?</b>

______________
Who's the man with the master plan?

 

[Ned_Flanders]

Oh, and if you're not aware - I'm running:

AMD64-3200+ Winchester Core CPU
1 Gig Patriot Low Latency DDR400 RAM
MSI Neo Plat 2 Motherboard
Akasa PaxPower 400W banded PSU (All rails are good)


______________
Who's the man with the master plan?

 

[jammydodger]

Maybe the memory controller cant handle that speed?

 

[Ned_Flanders]

I'm not too sure. Sorry, I did forget to mention that @ 2.45Ghz, the RAM is at DDR480.

Another odd thing is that, I know my RAM is stable at DDR520 (CAS2) but my PC will only boot at 2.45Ghz with the RAM running at CAs2.5?!

______________
Who's the man with the master plan?

 

[scottchen]

So when you say your ram is rated for DDR400 and it can do DDR520 meaning you've used a lower multiplier on the CPU and ran the system with higher HT? If not so, and you've simply ran the ram on another setup and could hit 520 doesn't mean it could hit on your current setup.

I'm really confused by your statement on your ram.

 

[Ned_Flanders]

Yeah, lowered the multiplier

______________
Who's the man with the master plan?

 

[ChipDeath]

I find my RAM's weird, if it's any consolation.

Even though it's only running single channel, I still need WAY slacker timings that it's rated for, and it's not even running at full rated speed :frown: .

The slower of the two sticks (512Mb Corsair XMS PC4000) is supposed to do 3-4-4-10 at 250Mhz, yet I can't boot at those settings even at 209Mhz, no mattter what I do. And 1T is a complete no-no.

And my latest BIOS, although it solved my memory speed issue, seems to have a minor bug. With the old BIOS, if I pushed settings too far it would give a Beeep... beeep....beeeep... 'Overclocking' error, but if you just turned it off & on it would boot in a 'safe' mode, and pop up a message telling you to go into the BIOS and change the settings. The new BIOS does the same, but seems to hang when it should pop the message up. Just means you have to open her up and reset CMOS manually, which is a little irritating.

I think the ODMC on these things is horrendously fussy basically, which is why we have these memory issues.

---
A64 3200+ Winchester @ 250x10= ~2.5Ghz, ~1.41 Vcore
1Gb @ 209Mhz, 2T, 3-5-5-10
Voltmodded Sapphire 9800Pro @ 450/350 w/ modded VGA silencer 3.

 

[Ned_Flanders]

update - get get 2.6Ghz0, but with a crappy divider!

Im think I know the answer already but:

What is faster overall:

2.6Ghz with DDR 360

or 2.45 with DDR 480

______________
Who's the man with the master plan?

 

[ChipDeath]

I suspect the 2.6Ghz will bench higher. I found that when I was first fiddling with mine.

Can't remember exactly what settings I was trying, but I think I got ~242Mhz / 2.42Ghz with a 1:1 divider and compared it to 2.6Ghz with 5:6, and the faster CPU with slower RAM was better in benchies. (This was before I got another stick of RAM, and the 1:1 was slacker timings and 2T of course).

I think I listed the scores in a post on here somewhere, I'll see if I can dig it up.

---
A64 3200+ Winchester @ 250x10= ~2.5Ghz, ~1.41 Vcore
1Gb @ 209Mhz, 2T, 3-5-5-10
Voltmodded Sapphire 9800Pro @ 450/350 w/ modded VGA silencer 3.

 

[ChipDeath]

found them...

<pre>--Benchies--

3x260, 2.6Ghz 1.51V (1.55 in BIOS); Ram @ 216Mhz 1T 3-3-3-7
DoomIII Demo 1 = 35.1FPS (second run)
3dMark 2K1SE = 21351
Folding@home = 8472

---

4x250, 2.5Ghz 1.46V (1.5V in BIOS), Ram @ 209Mhz 1T 3-4-4-10
DoomIII Demo 1 = 35.1FPS (second run)
2K1SE = 20708
Folding@Home = 8264

---

4x241, 2.4Ghz, 1.47V, Ram @ 241Mhz 2T 3-5-5-10
DoomIII Demo 1 = 35.1 (suprise!)
2K1SE = 20394
Folding@Home = 7944
</pre><p>

So there ya go... the 200Mhz extra on the CPU added 1000 '01 points, but it's hard to tell how much of that is down to the crappier timings at the higher RAM speed.

Guess the only way to really tell is to do a lot of benching.

---
A64 3200+ Winchester @ 250x10= ~2.5Ghz, ~1.41 Vcore
1Gb @ 209Mhz, 2T, 3-5-5-10
Voltmodded Sapphire 9800Pro @ 450/350 w/ modded VGA silencer 3.

 

[Ned_Flanders]

Ahh, thanks. Look like iI'm in for a bit of benching when I get the chance. Thanks for the info - but for now, I have 10 hours to do a piece of coursework that was set 3 months ago!

______________
Who's the man with the master plan?