Advice for overclocking

[Link19]

I am thinking about overclocking my system. I have a Pentium 4 3.0GHz w/800MHz FSB, 1GB of PC3200 Corsair XMS RAM (2 * 512MB DIMMs) in dual channel configuration, ATI Radeon 9800 Pro 8X AGP video card, Gigabyte GA-8IK1100 motherboard with Intel 875P northbridge chipset, and an Antec TruePower 550WATT PSU. Is it worth all the trouble and hassle to overclock everything on my system including the FSB and RAM speed with the CPU speed, or should I just try and overclock the CPU internal clock speed and leave the FSB and RAM speed the same? Would I need faster RAM and a new motherboard fan if I want to overclock the whole system, or can the Corsair XMS PC3200 RAM handle running at a faster speed with the FSB? If I do overclock the FSB, RAM, and CPU speed at the same time, will the PCI bus and AGP bus run at higher speeds too that could casue problems? What kind of fan should I get for my CPU and for my motherboard if I need a new one for the FSB speed overclocking?

Help greatly appreciated.

 

[WA261]

" 1. Get an Intel chipset
2. Lock pci bus to 33 mhz, and agp bus to 66 mhz
3. Start raising fsb in 5 mhz steps.
4. Repeat as necessary, or until system becomes unstable
5. Raise vcore to a max of 1.7v, but 1.65 is much safer and usually yields almost as high of a clock
6. Run Memtest86 & Prime95 torture test to test for stability at each frequency "

 

[wkabel23]

It appears you're a little mixed up about overclocking.

To OC a P4 you raise the FSB. I'm assuming the 3.0C uses a 15x multipler. You'll see that your front side bus is 200MHz. Say you wanted to get 3.5GHz, you'd have to up your FSB to 233 which is DDR466. I doubt your XMS can run that fast which is why you'd need to use a 3:2 or 5:4 divider depending on how OCable your RAM is. I don't know much about your motherboard so I can't comment on how it overclocks. With Pentium 4s you can't just raise the internal clock frequency (i'm pretty sure ). Check and see if your motherboard has an option to lock the agp and pci frequencies at 66/33. If it does and you plan on OCing you'd want to enable this. In the limited overclocking i've done i've noticed performance increases, so IMO it's worth it. Retail HSF will be good up to a certain point. How high do you want to OC your 3.0C? I believe anandtech is releasing an article on OCing very soon so you might want to wait and read that before you try overclocking.

Of course I left out a few things but if you have anymore questions someone will answer them.

BTW: If my terminology is incorrect, correct me...I hope I still got the point across

 

[myocardia]

Wow, you have the perfect overclocking system (besides the mobo), and you built it by accident? Why not just give it to me? If you decide to keep it, just do what WA said, except #1, and after you raise the fsb a little, you'll need to reduce your ram's speed. Corsair XMS will usually only run up to about 220 (440 DDR). I would definitely set it at a 5:4 divider, because you want to run the ram as close to 200 as you can, or your performance will suffer.

 

[Link19]

One question I have is why is the FSB speed said by Intel to be 800MHz, but it is really only 200MHz. I notice that it says 3.00GHz (200*15) on the POST screen when my system is booting up. I typed 200*15 on the calculator, and I got 3000 which is the internal clock speed of my CPU. I tried 200*16 and I got 3200 which would make sense to be a 3.2GHz P4. So does a 3.2GHz Pentium 4 have a clock multiplier of 200*16 and a 3.4GHz P4 has a 200*17 and so on for all Canterwood Pentium 4s with a 200MHz FSB (800MHz???)? I have heard that they say it is 800MHz because it is really 200MHz FSB quad pumped to make it 800MHz FSB effectively? Is that right? Is that is the case, if I increase the FSB to 250MHz, then would my performance be equivelent to a PC with a single pumped 1000MHz FSB? Also I'm pretty sure that if I just increase the clock multiplier from 15 to 16, or higher, I will only be overclocking my CPU internal clock speed and the FSB and RAM speed will remain the same right?

 

[wkabel23]

Originally posted by: Link19
One question I have is why is the FSB speed said by Intel to be 800MHz, but it is really only 200MHz. I notice that it says 3.00GHz (200*15) on the POST screen when my system is booting up. I typed 200*15 on the calculator, and I got 3000 which is the internal clock speed of my CPU. I tried 200*16 and I got 3200 which would make sense to be a 3.2GHz P4. So does a 3.2GHz Pentium 4 have a clock multiplier of 200*16 and a 3.4GHz P4 has a 200*17 and so on for all Canterwood Pentium 4s with a 200MHz FSB (800MHz???)? I have heard that they say it is 800MHz because it is really 200MHz FSB quad pumped to make it 800MHz FSB effectively? Is that right? Is that is the case, if I increase the FSB to 250MHz, then would my performance be equivelent to a PC with a single pumped 1000MHz FSB? Also I'm pretty sure that if I just increase the clock multiplier from 15 to 16, or higher, I will only be overclocking my CPU internal clock speed and the FSB and RAM speed will remain the same right?

Pretty sure multipliers on P4's are locked.

 

[apoppin]

Originally posted by: Link19
One question I have is why is the FSB speed said by Intel to be 800MHz, but it is really only 200MHz. I notice that it says 3.00GHz (200*15) on the POST screen when my system is booting up. I typed 200*15 on the calculator, and I got 3000 which is the internal clock speed of my CPU. I tried 200*16 and I got 3200 which would make sense to be a 3.2GHz P4. So does a 3.2GHz Pentium 4 have a clock multiplier of 200*16 and a 3.4GHz P4 has a 200*17 and so on for all Canterwood Pentium 4s with a 200MHz FSB (800MHz???)? I have heard that they say it is 800MHz because it is really 200MHz FSB quad pumped to make it 800MHz FSB effectively? Is that right? Is that is the case, if I increase the FSB to 250MHz, then would my performance be equivelent to a PC with a single pumped 1000MHz FSB? Also I'm pretty sure that if I just increase the clock multiplier from 15 to 16, or higher, I will only be overclocking my CPU internal clock speed and the FSB and RAM speed will remain the same right?

Let's try ONCE more:

Raising the FSB is the ONLY way to raise the cpu's internal clock on a (locked) P4. The multiplier is LOCKED except engineering samples.

Your ONLY choice is to raise the FSB as fas as it goes, taking care not to push either your CPU or your RAM too high - You'll notice the temperatures go up and your system becomes UNstable - back down to the last stable setting and/or raise the v-core slightly. That's why there is a 5:4 divider so the memory can still function with an extremely O/C'd FSB.

You MUST lock the AGp/PCI if the option is available on your MB or your O/C will be rather limited.

Yep, quad-pumped for an effective 800 FSB.

 

[Link19]

Why does Intel lock the clock multiplier on Pentium 4 CPUs if you can overclock the whole system using the FSB anyway? So safety couldn't be the reason then as it is more dnagerous to breaking your system to overclocking everything as opposed to overclocking only the CPU internal clock speed?

 

[apoppin]

Originally posted by: Link19
Why does Intel lock the clock multiplier on Pentium 4 CPUs if you can overclock the whole system using the FSB anyway? So safety couldn't be the reason then as it is more dnagerous to breaking your system to overclocking everything as opposed to overclocking only the CPU internal clock speed?

I dunno, possibly to encourage some enthusiasts to Xperiment with the Athlon platform.

So, howz your o/c so far?

 

[Link19]

What kind of fan, heat sink, and thermal paste should I get for my CPU and motherboard that is best for keeping things as cool as possible and is reasonbly quiet?

 

[myocardia]

If you are interested in going all the way to a 250mhz fsb, you aren't going to be able to do that with the stock heatsink, since that's 3,750mhz (3.75ghz). You should buy yourself a Thermalright SLK-947u heatsink and a Vantec 92mm Tornado fan for it, if you are planning on going higher than about 3.3-3.4ghz. The SLK-947u with a 92mm Tornado fan is good for up to about 4.0ghz. BUT, how do you know how high your board is going to let you clock that 3.0C? What we do is make sure the chip and mobo will go that high, then buy a cooling upgrade if we need to.

 

[Link19]

Originally posted by: myocardia
If you are interested in going all the way to a 250mhz fsb, you aren't going to be able to do that with the stock heatsink, since that's 3,750mhz (3.75ghz). You should buy yourself a Thermalright SLK-947u heatsink and a Vantec 92mm Tornado fan for it, if you are planning on going higher than about 3.3-3.4ghz. The SLK-947u with a 92mm Tornado fan is good for up to about 4.0ghz. BUT, how do you know how high your board is going to let you clock that 3.0C? What we do is make sure the chip and mobo will go that high, then buy a cooling upgrade if we need to.

Is this fan really loud, or is it reasonably quiet like the Intel fan that comes with the retail box Pentium 4 800MHz FSB CPU? Also if I want to overclock my FSB to 216MHz, will I need extra cooling for that and faster speed RAM? What about the motherboard cooling? Do I need a better fan and heat sink for the motherboard to be able to handle the faster FSB speed and keep it from over heating? Is it safe to test overclocking to see how much my motherboard, RAM, and CPU will handle without putting extra cooling on for a temporary period? The reason I ask is because like you said I should test first before I go out and buy expensive heat sinks, fans, and RAM.