Athlon XP mobile 35 & 45 watt advice needed

denh · Post by **denh** » Thu Dec 02, 2004 9:29 am

I have a few MSI K7N2G boards. The voltage is somewhat adjustable but I never had any luck undervolting my processors. What will happen when I put in an Athlon 2400+ mobile 45 watt chip? It will want to run at the 45 watt Mobile Athlon default of 1.45 but the motherboard goes no lower than the Duron default voltage of 1.55. My mobo may insist on running this mobile at no lower than the XP default of 1.65.

Can anyone tell me what to expect if I buy a mobile Athlon 2400 from New Egg? 45 watt and 35 watt.

Thanks
Dennis

Jordan · Post by **Jordan** » Thu Dec 02, 2004 5:23 pm

If you go into the VCore options in the BIOS you will see your lowest VCore setting. If it's 1.55V then the Mobile XP will run at that. To get the temps lower you would have to underclock it.

Jan Kivar · Post by **Jan Kivar** » Fri Dec 03, 2004 1:39 am

Jordan wrote:If you go into the VCore options in the BIOS you will see your lowest VCore setting. If it's 1.55V then the Mobile XP will run at that. To get the temps lower you would have to underclock it.

That's not necessarily true. Some BIOSs identify the CPU and show voltage options based on that (in order to prevent too high overvolts, so maybe this doesn't apply here?).

Cheers,

Jan

denh · Post by **denh** » Fri Dec 03, 2004 6:45 am

My question is can the 45 watt 2400+ mobile Athlon tolerate running at the default Athlon voltage of 1.65? I suspect the answer is yes..... How about the 35 watt mobile which I think runs on a default voltage of 1.35?

Will using the 45/35 watt mobiles just take good CPU cooling and I end up with an over clocked mobile Athlon? Though my real goal is a quiet machine. I wish my board under volted to 1.45v. I would not be posting here.

Maybe I should just get a desktop 2400+ Athlon and stop playing games with the mobiles.

Is any desktop 2400+ Athlon preffered?

Thanks all!

Edward Ng · Post by **Edward Ng** » Fri Dec 03, 2004 6:59 am

Yes, they can tolerate higher voltages; I ran my 35watt Mobile Barton for months at 2.156V and 2640MHz.

-Ed

denh · Post by **denh** » Fri Dec 03, 2004 7:59 am

Thanks much for the insight, Ng! Plus I liked the photos of your home built computers on your website

Dan

Post by **Rusty075** » Fri Dec 03, 2004 9:07 am

Putting these mobile chips into unknown motherboards can be a tricky thing. There's no real good guide as to how a new motherboard type will react.

Mostly likely it will limit you to the same BIOS options for voltage that you see now, with 1.55 being as low as you can go. While not as nice as being able to drop to 1.1v like you can on some other motherboards, it's still better than running a desktop chip, since you have full control over the FSB and Multiplier too.

Going from the mobile default of 1.45 to 1.55 will only bump your wattage by 6 watts, which is really pretty small.

There are a couple of other options for you too:

Software. 8rdavcore has some support for your mobo. That might let you drop the vcore lower than you can in the BIOS. (but you won't know until you try, unfortunately)
Get a new mobo.

There are lots of motherboards that are known to undervolt well with the mobile chips. You could sell/trade one of your K7N2G for one of them. (have a look at the NF7-S if you go that route)

Tephras · Post by **Tephras** » Fri Dec 03, 2004 3:01 pm

So I assume there will be no benefit in using a 35W XP-M over a 45W XP-M if the motherboard can't go lower than 1.55V?

Jordan · Post by **Jordan** » Fri Dec 03, 2004 4:41 pm

"My question is can the 45 watt 2400+ mobile Athlon tolerate running at the default Athlon voltage of 1.65? I suspect the answer is yes..... How about the 35 watt mobile which I think runs on a default voltage of 1.35?"

What you have to remeber is that Mobile XPs are actually just regular XPs made on the same productions line. They are then selected as XPMs due to their ability to achive the required clock speeds at a lower voltage and therefore thermal output. The multipliers are left unlocked and they are sold as XPMs. So if a regular XP runs at 1.65V a mobile will do it easily. Mobiles can usually take more voltage than a regular XP too.