Shuttle SN21G5 - Overclocking

[fighterpilot]

Just bought an SN21G5 to replace my SN95G5 since I wanted a PCI-Express video card.

I previously had no issue running my Opteron 175 overclocked in my SN95G5 to 2.64GHz, with a slight voltage bump.

Now that I am running my SN21G5, it will not overclock. I can get it to 2.42GHz, and with no voltage bump. I think the voltage change does not do anything! How I know this is because even if I leave it at stock speeds, and bump the voltage, there is no indicated voltage change in CPU-Z, whereas on my SN95G5 it would.

Before I go and bitch at Shuttle, could there be something else I am missing?

I have underclocked my memory to rule that out and bumped my HT multiplier down to 4x so as not to stress the HT path.

P.S. Normally I would post at sudhian.com but their forums have been down for a couple days. They seem to be the best crowd for Shuttle issues, but I know there's some knowledgable folks here as well.

 

[Dadofamunky]

Shuttle is not known for their overclocking prowess, and I doubt they'd even respond to you if ya tried.

My experience with the St20G5 in my sig is very similar. Except that the BIOS in my ssytem doesn't support the HT multiplier (strange). I can't get a stable 2.3 GHx overclock, so I'm running all stock. I'm still really happy with the thing, runs for days without a hiccup, which is mroe than I can say for my Intel XP boxes at work.

You might like reading this thread I created a month or so ago.

http://forums.anandtech.com/messageview...atid=51&threadid=1805915&enterthread=y

I think getting to 2.42 GHz Prime stable is actually really good for an SFF. You get a processor speed grade bump for free.

I DEFINITELY don't advise bumping the voltage. I don't really trust the L-shaped heatpipe cooler in the Shuttles. My CPU runs pretty hot because I value QUIET over 5-10 Degrees C.

Was your cooling unit aluminum? I wish they'd upgrade them to copper and sell them aftermarket. Coming from an XP-90C, I think their CPU cooling kinda sux.

 

[wwswimming]

i have a P4 3.06 GHz in a Shuttle SN40-something, the kind where you can see the front of the DVD-ROM.

it held a 3.61 GHz OC for a few hours. then i got in a one sided argument with a brother (he yelled,
i listened) and forgot about it. next morning it had re-booted. still runs good, knock on wood.