Undervolting an XP-M Mobile Barton for SFF

Ionizer86

Diamond Member
Jun 20, 2001
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I'm building an SFF soon (Shuttle SN45G) and instead of doing heavy 2.4GHz+ overclocking like on a desktop, I'm looking to undervolt as much as I can while still running at a reasonable speed.

My experience with XP-M's thus far has only been my desktop setup. XP-M 1700+ (T-Bred B) 0318 stepping. In the overclocking department, I was able to get 2.1GHz stable on 1.55V, and upping it to 1.60V didn't help. It started getting unstable (probably because it's summer in Florida now) so I undervolted as much as I could (which is 0.10V below stock on my EPoX 8RDA+). At 1.40V, it's stable at 166*11 right now (1.83GHz). I'll try upping the multi more later.

So anyway, does anyone who have a Shuttle know how undervolting on such a system is? Like on my desktop, I can only undervolt 0.10V from stock. If that's true, I'm probably looking at a 35W 1.35V Barton then. I'm thinking of getting the 2200+ for $77, unless the advice is to get a different chip, like a 2400+ 35W or something else.
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Those chips run at 1.45 V stock and you want to undervolt?

Why?

If you can't pull passive cooling with that, I doubt it would help you much to undervolt more.
 

Ionizer86

Diamond Member
Jun 20, 2001
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Well the 35W ones I'm looking at run at 1.35V default. My current XP-M Tbred does 1.50V default, but I have it at 1.40V (maximum underclock) anyway. Hey, it's summer, it's Florida, my current config was not fully stable, and getting over 1.8GHz at 1.40V is pretty reasonable for me! :)

The thing is, the Shuttle XPC box has no CPU heatsink fan per se. Instead, the heatsink uses a heatpipe to extend up to where the exhaust hole is, where one fan serves as both the heatsink fan and exhaust fan. The cooler the better, though I'd still want decent (1.8+GHz) speeds on the CPU.
 

Ionizer86

Diamond Member
Jun 20, 2001
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Since the 35W 2200+ Bartons came in stock, I jumped and bought one (along with the free alarm clock gift). I'll see how well the chip does once it comes in sometime next week :)
 

Gillbot

Lifer
Jan 11, 2001
28,830
17
81
Keep us informed. I'm actually considering tha same thing since my 1.4G T-Bird was WAY too hot in my SN45G. I opted for a 1.8 Duron but I think i'm gonna get a 35W mobile here soon.