XP-M 2500 : An OC query

I've just dropped a XP-M 2500 into my gf's machine after cooking the XP2600 during the recent heatwave. The motherboard I am using (ASUS A7V8X) doesn't natively support the M-series CPU's but is happy enough to allow some manual fiddling.

Minimum voltage on the board is 1.575v which, having read many OC threads, is way below what the chip is capable of but above its standard setting. Also while the board is happy to allow me to fiddle the FSB up to over 200 I'd rather stick to 166/33 as the memory is pretty standard (PNY & Crucial).

Currently the settings are 1.575v 166x12 (giving 1992) with no other alterations.

Temperature is 40deg at idle with a Coolermaster Aero 7+ (I just happened to have spare) running at full pelt and the system seems stable.

One issue however is when running test with SiSoft Sandra 2004. It moans that the core voltage is set too high for the model of CPU I'm running.

I'm not an overclocker normally so forgive me this stupidity but is Sandra OC savvy or is it getting it's knickers in a twist over nothing? I assume the later but would like to be sure so any light you can shed would be appreciated.

What voltage should I be running? I want to drop the fan speed and raise the temp slightly to make it more livable but should I expect to get more performance at the same voltage or am I best leaving it well alone for now?

Ta in advance :)

One of my housemates has that board so I lent him an old 2500+ mobile chip of mine to see what it could do. Not very much it would seem. It could post and superpi 1m up to about 166x13.5mhz (roughly 55s i think) but wouldn't go any further and just wasn't stable.

The reason sandra moans is that it thinks that the stock voltage for the mobile chip is 1.45v for 2500+ (133x14) which is correct but the mobile chips are exactly the same as the desktop chips which ran at 166x11 with 1.65v but are the highest quality chips of the bunch so were selected for the laptops where they could run with less power.

These mobile chips are pretty resilient and provided you have good enough cooling which will keep it under 50c load then they can take up to 1.85v. 1.85v is more or less the reliable limit for socket A boards and after then the voltages won't be very stable unless you volt mod them. They can take far more voltage than the new 64bit processors and as far as I remember you probably won't have a high enough voltage option on the a7v8x to do much more than confuse it let alone kill it.

Thanks for your advice.

I've poped the voltage at 1.675v for now with 166x13 to give 2.158 and all seems well. Idle sits at 53deg with is a little high but as long as it doesn't crack 60deg on a warm day under full load I'll be happy. :)

wow... 53C idle.. that IS a little hot.. I remember my XP-Barton did 2.3Ghz on 1.7V only had an idle temperature of 40's... load peaks around 58C... Try running it on Prime to see if it breaks 60C... I'm betting 8/10 it does... Nice VTEC sig...

With a thermal right si-97, as5 and a 120mm fan glued onto it I was getting 45c full load at 2v and 250x10.

53c idle is a little hot as that will rise close 60 even when doing light work for a short period of time and well above 60 when gaming....

Running 4 XP 2500 Barton Ms in Asus A7M-266D duals.
Run at an easy 2400 Mhz on 1.64v but FSB is limited on these boards to around 145 (no pci/agp locks). With Thermalright 800s run quite cool at around 45C in a rather hot box.
Good cores go to 2.5Ghz on 1.8v but run a bit hot. 2.4 Ghz is easy on 1.64v for most boards.

The xp2500m is a great chip for overclocking, it's what I've got in my games pc right now

Mine runs at 2500mhz (12.5x200, the absolute limit of the motherboard I'm using, which struggles to reach 200mhz fsb) with 1.75 volts. I did have to buy a thermalright si97 to get decent temperatures with it, but it currently idles around 40 and reaches a load temperature of around 60


with your pc, you should probably look into improving the cooling since heatsinks like the si97 do a much better job, the voltage isn't really a problem since it only seems to affect heat and not long term functionality.
It depends on the chip as to how far it'll go but the xp 2500+m (and the other mobile chips) were definitely the best for overclocking on the socket A platform and wouldnt have much trouble running at around 2400, maybe 2300 at the worst.

Interesting stuff.
You're all right about the temperature, I'll try and drop the voltage and see if it remains stable.

Many thanks to all.

I don't think its the chip however, I've tried overclocking with that motherboard and unfortunately i think its not the best overclocker. Think it has an AMI bios which isn't much use.

If you're looking for a good motherboard by far the best to get is the DFI lanpart nf2 ultra B. Its made by the same company thats boards are the best for athlon64 overclocking is the only nf2 board that will get you above about 230mhz fsb. They also have voltage options for everything and are incredible easy to overclock. My 2500+m would do 2300mhz with 1.70v, 2400 with 1.75 and 2450 with 1.80 and 2500 and 2600v with 2v. Needed a bit of a jump in voltage for 2500 and 2600 but it didn't do the chips any damage. Was getting 37-39 seconds for superpi 1m so quite nice for an old processor!

Abits NF-7s is also worth a look but I don't think its quite as good. Both could be had on ebay for about £30.