New to OC'ing and have a question about FSB

[BillClo]

I am new to overclocking, and have a question. I have not yet unlocked my Athlon XP processor, and wanted to just try raising the FSB for now. I am unable to get the FSB past 137 mhz, 138 and up, it locks up.

I am using: Athlon XP 1900, Epox 8KHA+, Corsair XMS2700 mem, Hercules GF2 GTS, Phillips Sound card, and a Linksys network card...

Temperatures are about 106 degrees (CPU), 75 system - according to BIOS anyways.

I've tried changing the memory latency from 2 to 2.5, no difference.

Is one of these components holding me back, or is something else?

 

[WaTaGuMp]

There are many things that can keep you from going higher. Some chips do better then others some settings can be changed to help like uping you voltage etc etc. Its all trial an error. Your PCI bus speed is increased also when you o/c so you can make sure that your PCI divider is set right if its not done automatically on your board.

 

[MentalAtrophy]

Definitely need to up the voltage to the processor, that'll help stabilize over 140mhz fsb easy

-mA

 

[BillClo]

What's the safe max voltage for an XP processor? Board maximum, or something else? Is there a rule of thumb whereas you increase voltage x amount for x amount of FSB increase?

I figured that there'd be lots of trial and error, but wanted to keep the variables to a minimum...

 

[hovenas]

Up it in small increments... test for reliability, If it works, keep it there! I have set 146 MHz as max on my board because I don't want to damage my AGP/PCI by taxing them at too high bandwidht. I have upped 0.05 volts and now runs stable.

 

[dunkster]

Personally, I work on optimizing memory throughput first.

Then working up the FSB to find the sweet spot with best combination of higher FSB and good memory throughput.

For FSB-overclocking, incrementally increase FSB clock speed until unstable, then increase VCore for stability at that speed. Repeat that process until increasing VCore will not help stability. Any Vcore voltage above what's necessary for stability only adds heat to the cpu.

Same goes for DDR voltage. Any voltage over what's needed for stability just increases likelihood of failed memory due to heat.

I have a poor-quality xP1600 (AGKGA stepping) that is unstable with VCore over 1.8V. I'm stuck at game-stable 148MHz fsb max with Vcore of 1.775V.

I have Corsair XMS2400 at 2.65V ddr voltage, all dram timings maxed except 2T command rate. Corsair is good stuff - really wasted on this crappy xp cpu.

Hope this helps!

 

[MentalAtrophy]

As for maximum voltage, AMD recommends no more than 1.85vcore, but it's been done up well over 2v with extreme cooling systems. The DDR voltage can go up to 2.75v but i try to be more careful with that because it has no active cooling. As long as the processor stays cool and you're not trying to pump over 1.9vcore without a freezer in it then you should be fine.
My 1.6ghz runs at 1.74ghz w/ 145mhz FSB at 1.85vcore, 2.55v ddr stable. Idle temp for me is < 30C and rarely gets over 38C.

-mA

 

[RaynorWolfcastle]

<< I have a poor-quality xP1600 (AGKGA stepping) that is unstable with VCore over 1.8V. I'm stuck at game-stable 148MHz fsb max with Vcore of 1.775V.
I have Corsair XMS2400 at 2.65V ddr voltage, all dram timings maxed except 2T command rate. Corsair is good stuff - really wasted on this crappy xp cpu.
Hope this helps! >>





Hmmm... I think you just had bad luck with the XP 1600+, I have an AGKGA 1600+ that runs at 150/150 stable (1575 MHz) without touching the voltage and running on a retail fan

MentalAtrophy what stepping is that Athlon XP 1900+ ? What heatsink are you using? That's a pretty fair OC considering those temps

I agree that increasing the CPU and memory voltages should help stability, but I personally tend to shy away from it since I keep my CPUs for 3+ years.


- Ice