AMD athlon XP 2500+ barthon @1.85Ghz (166 * 11)

**Dino_Martino** · May 29th, 2011, 04:54 AM

Hi again!!
I've got a descent computer, but it's getting a bit old. So I'dd like to OC it a little bit.
I haven't checked my clockgenerator or anything, because I was wondering whether I can't just increase the multiplier.
My MOBO has got jumper settings to increase the multiplier, but what risks are there?

CPU: AMD athlon XP 2500+ barthon @1.85Ghz (166 * 11)
MOBO: K7S41GX (A-socket)
RAM: DDR SDRAM

Can I simply turn the computer off, unplug it, change the jumpers, and turn it on again?
Thank you.

**ShyguyXPC** · May 29th, 2011, 05:26 AM

Shouldn't be jumpers for changing the FSB/CPU Clock Multipliers on that board, if there is, its a bit odd, as by the time that board came out, much of that stuff was done with in the Bios.

This is your board, right? ASRock > Products > K7S41GX

If you can do the changes in the Bios, you should be able to make changes, save it, reboot PC see if it will boot or not, then test each change for stability with something like Prime 95 or something.

Another thing you could try instead, is bumping up the FSB speed instead.

166 (DDR 333 Effective) x 11 = 1826MHz

200 (DDR 400 Effective) x 11 = 2200MHz

Just a mere 33MHz FSB bump gets you that nearly 400MHz CPU Clock increase.

Do you know what your CPU's max Clock multiplier is?

I know my Athlon XP 3000/3200 Mobile Model, has a 16.5x Max Multiplier, but runs a 266MHz DDR FSB (133MHz FSB), so only runs at 2.2GHz-ish stock (2195MHz). With that high of a Clock multiplier, hypothetically/theoretically, if all the planets came into alignment, on a 200MHz FSB with that Multiplier that thing could get 3.3GHz... not that it can, or if I have ever gotten it that high, have never had a stable enough board to get it to run beyond its stock speeds much. But I haven't messed with it in years.

As to risks, well with OCing as always, you could potentially burn out the chip, but not likely unless you did something stupid like heavily overvolting the CPU, crappy unstable, unclean power supply, lack of proper cooling (air flow, heat dissipation, thermal paste applied wrong, heatsink not properly attached, etc)

but most common is that the PC won't boot or will boot, but won't run the CPU at load or partial load with settings, in which case either you revert back to original specs, or worst case scenario, you just reset the CMOS, restore bios to stock, and try again.

**ShyguyXPC** · May 29th, 2011, 05:29 AM

Back then in the Socket A era, CPU overclocking was so much easier (in that there wasn't THAT many options and tweaking things to do with them, you had your FSB and Clock multipliers, and various voltage controls, and then there was FSB and RAM timings for the RAM, now days, when you look at a board with heavy OCing options, all you can do is stare at it and wonder what the heck you should change first, so many options, settings, etc, it boggles the mind, and wonder why the heck does it have to be so damned confusing/complicated, despite the User interface and ease of adjustments have gotten so much easier)

**Dino_Martino** · May 29th, 2011, 05:37 AM

Ha, good point! Old&Gold

Yet I WHOULD trade it for a new one

My MOBO has got jumpers for the multiplier. I attached the manual.
I haven't gotten the chance to take a good look in the bios... (parents

)
I'm new to this PC, I've just started using it so I don't know it's Do's & Dont's yet.
I knew the risks of increasing FSB, but are they the same for multiplier?
What is preventing me from setting my multiplier to 24? (the manual says it can be done with the jumpers...)
Increasing the MP doesn't increase heat, does it? It only decreases stability? No risk of frying?
I know the theorem behind OC'ing, but I lack the practice.
Also, if I keep a good eye on my CPU temp, I don't risk frying it, right?
PS: I attached the MOBO manual.

**ShyguyXPC** · May 29th, 2011, 05:54 AM

Whats preventing you is that the CPU only has a max Multiplier number, the motherboard supports up to 24, if the CPU is capable of it, but I highly doubt your XP 2500+ Barton goes that high, the Mobile XP Barton like I have, these had some of the highest multi's available at the time, but because they ran at a lower FSB speed, they balanced out in performance to desktop versions which is what I think you have (Desktop versions had the higher 333 and 400MHz DDR FSB with lower clock multipliers)

Multipliers do increase heat, as it increases the overall CPU Clock speed as it does with adjusting the FSB, just that usually the Clock multipliers seem to have less of a increase on CPU clock than FSB does, but FSB adjustments are more precise and incremental.

take for example your CPU, bump it to a 12x and your running 1992MHz on a 166MHz bus.

keep it at 11x and bump it from 166 to 200, and your running 2200MHz, if the CPU will run at 33MHz faster.

usually you have to find a balance between the two to get it just right.

sometimes a CPU won't boot with too high a clock multiplier at a given CPU Clock, meanwhile it'll boot just fine if the Multiplier is left along and the FSB is increased to match that same CPU clock. each CPU is a bit different and need to play with it a bit to find its sweet spot.

Generally increasing the multiplier doesn't boost heat output as much as FSB does, in either case, you usually don't have to worry about it too much unless your OCing by a fair amount, or start Overvolting the CPU and RAM, increasing power consumption which generates more heat.

also keep in mind, on most AMD Socket A systems of the era, your RAM will be a limiting factor as well, most systems I know of didn't have a divider for the RAM, so as you boost your CPU/FSB speed, the RAM speed goes up as well.

If your running DDR 266MHz RAM you might be running into some stability issues with it, DDR 333 would match your current CPU FSB, but if you had DDR400 you have some OCing room, for a 333 FSB system. even if its DDR 333 right now, depending on the brand, and specs of the RAM, it may be capable of a decent OC.

in general I think it was normal for a good 20-30% or more OC on those CPU's though at stock voltages, and decent RAM & regular air cooling.

**Dino_Martino** · May 29th, 2011, 06:02 AM

my ram modules are PC3200(200Mhz).
Another question: Let's say I can run the computer stable at standard FSB with multiplier 13x (hypothetical example), and it can also run it at let's say 200Mhz FSb with standard multiplier.
Doest that mean it will run fine at 13x200Mhz?
Or can the combination of both make it unstable?
Do you understand what I mean (I'm sorry, I'm not a native speaker...)

Bottom line: what do you reccomend?
Leave the jumper settings alone and start fiddling with it in the BIOS?
Thank you.

**Dino_Martino** · May 29th, 2011, 06:04 AM

More info on my RAM:
1. 1024MB (1 rank, 4 banks)
Unbuffered
PC3200 (200Mhz)
Double density

2. 512MB
unbuffered (1 rank, 4 banks)
PC3200 (200Mhz)
Single density.

Will the double density RAM give trouble or stability issues?

**Dino_Martino** · May 29th, 2011, 06:24 AM

Also, I know I've got jumper settings for the multiplier, are there advantages to using the jumpers over the bios? more preformance, stability, safety, less heat, anything?

**Dino_Martino** · May 29th, 2011, 08:16 AM

Ok, figured out the bios!
In bios I can alter the FSB frequency, but not the multiplier.
If I want to change the MP I will need to buy some jumpers

I've got it clocked now at 200x11 and it seems fine. I've been running superpi for 10 minutes, and the temp has gotten up to 51°c.
What is the maximum safe and stable temperature for this CPU? (anything else I should monitor for safety?)
Thank you.

**Dino_Martino** · May 30th, 2011, 12:12 PM

My current FSB is 200 Mhz.
My RAM works at 200Mhz
Will I gain more preformance by OC'ing the FSB to 210?
Or whouldn't that matter since the RAM runs at 200?
thank you.
Also: is it ok for the northbridge to run very hot? (even with standard FSB?)
I just don't burn my finger at it (just...)

**stroyal** · May 30th, 2011, 01:00 PM

I've been running my Barton 2500+ @ 3000 for 8years now.
I have 400Mhz memory, and run 10.5 multiplier and a 200MhzFSB no voltage change.
I have a slightly beter than stock air cooler, and it runs from 32c to 38 c.
It is pretty hard to overheat a barton, I think the max is around 90c, but I'll look.

If I go any higher, I have to mess with the voltage.

You should have a fan on the north bridge, or a huge passive cooler, like I have.

**stroyal** · May 30th, 2011, 01:12 PM

Barton is 85c max

**Dino_Martino** · May 30th, 2011, 01:39 PM

Mine ran fine @ 200FSB with multiplier 11.
My northbridge is passively cooled, with a descent aluminum heatsink (stock).
Will a case fan in the back be adequate for the NB?
I haven't got a temperature sensor for it, but I can keep my finger on it for a minute without getting burnt.
What are the safe heat limits for this NB? And that 85°C, that's the absolute top right?
To stay well within the safe zone, around 65-70 max?

Perhaps I posed my question unclear.
Will running a higher FSB than memory speed increase preformance or whould that make no significant difference?
How does the barton handle higher multipliers? like 12, or 12,5?
Thank you for your good help so far!

**Dino_Martino** · June 3rd, 2011, 12:33 PM

I'm baffled.
I can't change my multiplier in the bios.
I found out that my MOBO has jumper settings for the MP. I installed the jumpers (that were absent before) in the 12x configuration, and my computer booted at 11x.
I suppose my multiplier is locked?
How can I unlock it?
thank you.

**stroyal** · June 3rd, 2011, 01:31 PM

I'm pretty sure there was no way to unlock the later ones, I'm sure a Google search would come up with one if there is one, I did find a wire mod for a mobile 2500+, but it said it didn't work for a desktop model
.Solution: Mobile Barton 2500+ and 13x multiplier and above - Overclockers Forums

You can also look up the numbers on the CPU, to tell if it is supposed to be locked or not.

**Dino_Martino** · June 3rd, 2011, 01:40 PM

You've got your MP set at 10... 11 is standard: You've got one of the older ones I suppose...
Damn.
Why whould they lock the MP in the first place? bastards...

**Dino_Martino** · June 3rd, 2011, 01:41 PM

I'm gonna stick to 11x200 than.
Anything else I might tweak to gain preformance?

**stroyal** · June 3rd, 2011, 02:30 PM

10.5,200fsb 2100Mhz and yes, it was one of the very first, but can't the locked ones clock lower, just not higher.
If it works I'd keep it at 11x200.
That's a pretty respectable over clock anyway.

**ShyguyXPC** · June 3rd, 2011, 03:53 PM

They locked the multipliers to boost sales of the higher end CPU's, this way people couldn't buy a $100-150 CPU and overclock it easily to a $200-300 model. all the low end bartons were being snatched up, and overclocked, leaving the high end ones sitting on shelves... which also drove up costs on those as well, due to low sales.

Locking the Multi's reduced those effects, but it was too little too late, as AMD was coming out with their Athlon 64 CPU's by that time.