Phenom II 545 & 550

[Nashsafc]

How much can a PII 550 BE overclock to. I have a Phenom II x2 545 and i have managed to overclock it to 3.7ghz stable. How much more can the 550 overclock to? A 545 at 3.6ghz i'm guessing is the same as a 550 at 3.6ghz? The unlocked multiplier doesn't give better perfromance for the same frequency?

 

[Devastator_uk]

Since the 545 and 550 have the same core, you'd probably only get the same frequency, if you're lucky 0.1GHz more.

As for the multiplier, the CPU itself has the same performance no matter how you achieve the core frequency, however on older CPUs increasing the bus speed and lowering the multiplier could increase performance because the bus was a serious bottleneck, although this could lead to stability issues as the RAM and PCIs would be overclocked. However on new CPUs (with HT or QPI) it makes little difference as there is usually plenty of available bus bandwidth, but increasing the bus could still affect PCIs/PCI-Es and so on.

 

[Nashsafc]

i just overclocked my processor. Funny things have been happeing, at first i thought 3.7 was reasonably stable. Then it goes into this blue screen that says memory dump, and says hardware has not been properly installed. Also my ram is Corsair DDR2 xms2 800mhz, but it is not overclockable. Does this mean anything. If i can't overclock my ram with the CPU does that limit how much i can overclock the CPU by? I have an xfx 8300 motherboard. I overclocked to 3.6ghz and it was running stable the couple of times i had my pc on. But now it keeps taking me into this blue screen eventually when i'm logged on in windows.

So wait, there's actually hardly any improvement really from the 550 compared to the 545 in overclocking performance? Could the memory dump error be something wrong with my memroy in relation to the overclock or the cpu overclock that i have clocked to?

 

[seabreeze]

...Then it goes into this blue screen that says memory dump, and says hardware has not been properly installed. Also my ram is Corsair DDR2 xms2 800mhz, but it is not overclockable. Does this mean anything. If i can't overclock my ram with the CPU does that limit how much i can overclock the CPU by?

Generally it won't limit most overclocks, so long as you keep it on Auto or lowest ratio for most ram modules. It rarely becomes an issue with HT.

So wait, there's actually hardly any improvement really from the 550 compared to the 545 in overclocking performance?

Unlocked multiplier on the 550 making it easier to choose a clock x multiplier at the speed you like, whereas the 545 is clock increases only. This doesn't necessarily mean the 550 is better than the 545 at the same speed. Both at 3.5GHz are likely to give you the same results, whatever combination of clock and mulitplier you use for the 550 (545 will be 233x15).

Could the memory dump error be something wrong with my memroy in relation to the overclock or the cpu overclock that i have clocked to?

Assuming your memory ratio is set as low as possible and is not operating beyond it's spec, then most likely your cpu overclock is not stable.

You've mentioned it was stable at 3.7GHz, or you thought it was, then BSOD. What applications have you run and for how long to determine system stability? It would be a good starting point to know this.

Lastly, "reasonably stable" is an oxymoron. Either it's stable, or it's not. Only testing will tell. Everyone has different ideas about how long and what with, just satisfy yourself that it is.

 

[amdfangirl]

How much can a PII 550 BE overclock to. I have a Phenom II x2 545 and i have managed to overclock it to 3.7ghz stable. How much more can the 550 overclock to? A 545 at 3.6ghz i'm guessing is the same as a 550 at 3.6ghz? The unlocked multiplier doesn't give better perfromance for the same frequency?

Just a bit more 'stable' cause your rasing multi, not core clock.

Then again I recommend lowering your HyperTransport Multi.

 

[seabreeze]

Yes, if approaching the upper limits of memory specification, lower the HT to 9 or even 8 and see how things go.

 

[Nashsafc]

it was working at 3.65 ghz. I was getting results from passmark. And i think i put it on a stress test under OCCT. But now it goes into a blue screen. I think randomly now even when i've overclocked it to 3.5ghz. There's nothing wrong with the temperatures, or the voltage. So i'm confused. Does the blue screen mean that the processor is just not stable at that frequency and i should accept it? Also i'm sure my bios is fully updated, i have an xfx 8300 motherboard and i have the 18.11 drivers installed.

 

[seabreeze]

The blue screen can mean a thousand things, but you should not accept it.

It's best to log data, even manually by writing it down, the critical parameters as you go.

Do you have an overclock that is known to work without any other changes except the clock? Go to those settings and use Prime95 for 10 minutes. If it's 235 or 240MHz go to that and run Prime95, see what the temps are as well.

If not, then the only known good configuration is stock, so clear CMOS and start again. Don't change ANYTHING except the clock speed in 10MHz steps. Leave voltage alone until it won't run Prime95 for 10 minutes or run some others you prefer.

It can be tempting to jump back in again at 250MHz or so, but it's best to approach the problem from the working side, rather than leap past it the problem and try to find your way back.

If you do that you'll have a good idea at what point where something other than clock speed needs to be changed, then change one thing at a time and test.

 

[Nashsafc]

how do i clear the cmos. Is it the jumper thing on the top. I just move it to pins 2 and 3 rather than 1 and 2? Is it just the top one as well? Or not move both of them? There is also another jumper thing at the top on it's own should i ignore that?

 

[Nashsafc]

there's two jumpers on the bottom of the board and one on it's own at the top

 

[Wisecracker]

I have no problem overclocking corsair xms 800.

Maybe your running your memory TOO fast and thats causing your blue screens.

When your at 3.5ghz, what speed is the memory running?

Pretty much this.

Drop your RAMs speed way back to completely eliminate it as a factor. Determine your highest CPU clock at the voltages and temps of your liking *** --- then begin slowing working your RAMs speed back up and checking for stability along the way.


edit: I fergit ...

*** Once you get the base clock in the 235-240MHz range you may want to drop the IMC/NB multiplier back a notch (and the HT multiplier, too) to eliminate them as an issue. When you find your sweet spot you can then start to tweak on the IMC/NB --- save your memory tweaking for last.

 

[Nashsafc]

i can't overclock the ram, the ram in the bios is not avialable for me to overclock. The ram is running at 936 mhz. With the processor at 3.5ghz. The fsb is 234 for that. The ratio for the ram is x2, and the multiplier for the processor is 15. I've concluded that 3.5ghz is stable as i've been playing command and conquer 3 for sometime with no crashes. You mean i should decrease the ram's speed, how? In the bios i can see the specifications of the ram that it is at currently, and also on Ntune as well but can not change them.

 

[Wisecracker]

What model motherboard?

If you are using a Gigabyte check your manual for how to open the 'secret' memory settings in the BIOS. Depending upon your motherboard version and BIOS you most likely will have two options:

1) Memory ratio: Drop from 400MHz to 333Mhz

This will reduce your RAMs speed from 936MHz to 780MHz with the base clock at 234MHz --- giving you additional headroom to up the base clock.

2) Memory dividers: AMD RAMs are 'double-pumped'. DDR2 800 runs at '400MHz X 2'. Some BIOS offer dividers in a fashion similar to this ...

2 X 400Mhz ---> 1:1
2 X 533Mhz ---> 1:1.33
2 X 667Mhz ---> 1:1.66
2 X 800Mhz ---> 1:2
2 X 1066Mhz ---> 1:2.66

In some BIOSs you may see dividers like this ...

2 X 400Mhz = 6/6
2 X 533Mhz = 8/6
2 X 667Mhz = 10/6
2 X 800Mhz = 12/6
2 X 1066Mhz = 16/6

 

[Nashsafc]

It seems to be with the fsb, when i raise the fsb it also raises the frequency of the ram. I've been overclocking with the bios and nTune. I have an xfx 8300 motherboard. So i should keep my memory running at 800mhz all the time? The memory ratio says it is 2.0x on nTune. But it can't be because the fsb is 200 at the moment and the frequency of the ram is 800. This is my first real attempt at overclocking you see lol.

 

[Nashsafc]

when you say "Once you get the base clock in the 235-240MHz range" Do you mean the FSB? Also when you say "IMC/NB multiplier" what do you mean lol? Where can i find these? Can i do this all in the bios?

 

[Nashsafc]

i seem to have changed something now and now it says memory at 468mhz, memory ratio 1.0x, fsb frequency 234. And the processor speed is at 3.5ghz now. Is this safe? But is this not an effective overclock? Is it possible for me to keep my memory running at 800mhz constantly?

Also , what is the HT. That also seems to have a frequency lol, currently it's at 2.16ghz with the cpu at 3.6ghz. The ram is at 638mhz now. Is that ok, should i have the HT frequency as low as possible? Please tell me about it

 

[seabreeze]

Hmmm...it seems you are attempting several changes (variables) at once and I get the impression the results are due more to good luck than good planning.

At least the ratio is down to 1:1. It should allow you to fiddle about with the cpu overclock for a while.

As suggested, it might be best for you to read some overclocking guides until you are faimiliar with the jargon, their settings (both stock and maximums) and their relationship to each other.

 

[OvrClkr]

The 550 will overclock to 4.0Ghz and beyond, it depends on mobo and cooling method you will use....

There are not many benchmarks for the 545 so I guess time will tell....