[Roofles]

I have a 845 (Northwood?) cpu that was stock at 2.20 Ghz , 22 Multiplier and 100 Mhz bus, now as far as i know that multiplier is locked, however I can, and have upped the bus to 110/111 mhz, which gives me a new clock of 2440 and change.

So, the question is 2 parts, 1. Anyone have the same cpu and what limits have they taken theirs too? and 2. are there any problems I should forsee about changing the bus?

[batboy]

The 845 is probably the motherboard chipset. Do you know what brand and model motherboard you have? If you can lock the AGP/PCI to 66/33, you can go higher. If not, then you will be limited to around 112 to 115 FSB.

[Roofles]

Yeah its a Gigabyte GA-8IPE1000 and yes I can lock the agp/pci to 66/33. Quick question though, what is that, and what does it effect?

[batboy]

AGP is the vid card and the PCI bus affects all the cards in the PCI slots, plus the IDE controller. Lock the AGP/PCI and crank it up. Just watch the temps. I've seen those 2.2 CPUs do 2.5 to 2.7 gig (if it's an older one).

[Roofles]

Har, I just realised i sounded retarded, yes I know what agp and pci is, i was just curious as to what the 66/33 was. Its stable at 2440 now and only runs 29 C idle

[batboy]

The AGP bus runs at a default 66 MHz and the PCI bus runs at a default 33 MHz. Locking them to 66/33 just means you fixed the frequencies to default speeds.

[Roofles]

Yeah that clicked in my head a bit later.

[Albuquerque]

To your question about the "limits of the 845" chipset, it's entirely dependant on your motherboard. I was able to run my old Albatron PX845PE Pro IIs motherboard to 208FSB stable, but at 209FSB it would start to come apart in memtest and prime. But I've seen other motherboards stop around 166-185 depending on manufacturer and model.

Since the 845 chipset is rated for 100 or 133FSB operation, getting it working at 208FSB is an effective 56% overclock. Not bad It would be equivalent to getting an 865/875 chipset running at 312FSB... Don't see too many of those

[Strages]

Well, your first problem is that either you don't have that motherboard, or you don't have an 845 chipset - because the board you say your have has an 865 chipset . Having a 110fsb on that board is not pushing it at all, the limitation is undoubtedly going to be your processor or RAM before your board. What is odd, is if you're reporting the correct FSB then you have one of two things - a wilamette core (which I didn't know worked on new boards, cause they were mainly socket 423) or a Celeron (which would suck - a lot). I would find out a bit more about your processor first. Obtain and run CPU-Z, it will give you all the feedback you'll need to determine what kind of processor you've got under the hood. That is going to help a lot in determining your potential limits.

[Roofles]

Ah I guess I threw too much information in there with out truely knowing what it meant.

The chipset on the Motherboard is 865, the processor itself is 845 with a Northwood core. No it is not a Celeron, its a P4.

I did download CPU-Z for what its worth. But oddly I noticed that my cpu core voltage jumps. I have it set within the mobo at 1.525, oddly though that CPU-Z shows that it goes from either 1.55x volts to 1.536 which seems to be a steady voltage.

Any thoughts?

[batboy]

Strages was correct about the motherboard. However, the 2.2 is definitely a Northwood (never heard it called a 845 before) and if it has 512k cache, then it's a P-4. Willamettes only went up to 2.0 and there were plenty of socket 478 Willamettes (although all 1.3 and 1.4 Willamettes were socket 423).

It's not uncommon for some motherboards to overvolt a little, especially at idle like Asus, while others like Abit tend to undervolt a little. Your vcore is fine.

[Strages]

Ok, well, I realized where I was mistaken - I didn't know that the first few northwood-based processors were 400FSB (100*4) models.
Anyhow, that motherboard is going to hold easily until you hit at least a 200FSB. Just make sure you have some decent RAM (DDR400 will guarantee you a 200FSB as long as your processor can handle it), after that some good cooling. Most coolers you can get now are going to be able to cool that chip really well, as it has a TDP of 55w - which by today's standards is extremely low. Basically, your only limitation is going to be your processor in this case (unless you have a freak processor that can go to a 300FSB or something insane ).

[Roofles]

Eh im working on that ram problem, heh. I have a 512 stick of 2700 and a 256 stick of 2100 which is doing some funny stuff with its speed. Computer works fine, but eh. Also on heat, it runs at 24*c idle up to 34-37 *C under load and also cools off reallly quick.

I wouldnt mind hitting 200 fsb, 22 x 200 = 4400 so i think that would be a nice clock . However the processor tells me its limit is about 2.8 ghz. I still would like to hit atleast 2.5, maybe 2.6.