Help With Mobo Voltage Issue

[Netopia]

Hey Gang,

I got in on the deal at newegg for a S754 3400+ and a very cheap Biostar mobo. The mobo has no settings for CPU multiplier and only has +1%, +2% and +5% for CPU voltage.

The default speed of the CPU is 2.4GHz. I can raise the FSB to 233, give the CPU +5% and the DDR 2.8v and I can boot at 2.8GHz. At that speed, I can boot into any of several Live Linux CDs. If I boot and do memtest86, even with the memory running at DDR466, it passes over and over. If I try to do any CPU stressing though... it hangs pretty quickly. I tried it at 230FBS for a speed of 2.76GHz and it takes longer, but will still hang on CPU stressing.

So... since I'm able to boot and do some GUI stuff at 2.8GHz with only 1.47v on the CPU, I'm thinking it must be a pretty good chip... I got lucky! I don't really want to dump another $60-70 on a decent motherboard, as that would sort of defeat having gotten in on this deal.. I would have just gotten an S939 and a decent motherboard.

So, my question is... does anyone know of any way to up the default voltage on these things? If I could get the default to 1.5, the the +5% would take me up to around 1.57 or 1.58 and I'm guessing that might be enough to get me the 2.8GHz stable. Even if it misses that mark, I should be able to get 2.76GHz, which would still be an outstanding overclock... especially for $99!

Any thoughts?

Joe

 

[myocardia]

You're either going to have to lower your overclock, or buy an overclocking motherboard, that has adjustable vcore. It's really that simple. BTW, 12x220=2640 Mhz. That's not too bad for $99.

 

[Netopia]

I'm actually looking stable at 225 * 12 = 2700MHz! But to be honest, so far from other reports, that seems a given if you have decent (not even great) memory. BTW... the memory is 1:1, so that sweetens it a little.

But I'm not so quick to give up. I remember that with other CPUs in the past, there were ways to connect a wire from one pin to another to up the voltage... stuff like that. I figured that it was worth at least asking.

Joe

 

[Netopia]

Any other ideas?

Joe

 

[myocardia]

Yeah, if you're wanting to go that direction, it's possible with Skt. 754 chips: link.

edit: Here's a bunch more, in case that one seems a bit too complicated: link.

 

[Netopia]

Mr :heart:!

Thank you much for the links. I've got some reading and playing around to do now. When I finally either success, fail or fry my cpu I'll post and let you know.

Thanks again,

Joe

 

[Netopia]

This link in particular is AWESOME!

http://www.ocinside.de/go_e.html?http:/...p/s754pinmod/amd_socket754_pinmod.html

Thanks!

Joe

 

[Netopia]

I dropped a wire in the socket according to faq above... worked GREAT. Went for 1.5v and ended up with 1.52. Upped the voltage in the BIOS and am now at 2.76GHz and running Prime95!



Joe

 

[Netopia]

Actually... now 2.8GHz is looking stable running prime95 on PuppyLinux.

Joe

 

[myocardia]

That's great, man. It's making your $99 invest look even better, isn't it?:beer:

 

[Netopia]

LOL.... it's making the $99 an absolute KILLER deal! I don't know that it will actually be stable once I load up Windows and its various drivers and such, but for now it's been cranking prime95 at 2.8 for about 5 hours without problem.

It turned out that even though the BIOS said +5%, it actually boosted the voltage from 1.4 to 1.55, which is actually 10.7%!

I started out figuring that a single strand of wire from a cat5 cable would do nicely... nice and fine but flexible. I couldn't believe it when it wouldn't even fit in the hole in the socket! I ended up having to take a piece of wire off the end of a fan pigtail and then picking out one of the strands from that... cut it to about 3/16" and had to hold it with a really small set of hemostats (roach clips to some people). It was hard working with wire that was about as thin as a hair, or maybe thinner. It would bend REALLY easily. But, I finally got it in and when I finally got everything up, default was 1.52, but I added a supposed 2% that raised it to 1.63v (actually 7.2%!).

It seems to be staying around 38-40C... though I can only tell by rebooting quickly and looking in the BIOS, as I don't have anything in Linux to tell me... so it could be cooler by the time I check.

What is considered too high? I'm up by almost a quarter volt, which is more than I used to use to get Celeron 366's up to 550!

Joe

 

[Netopia]

24 hours at 2.8 GHz with a Socket 754 running Prime95 and not a hiccup yet!

Joe

 

[DrMrLordX]

That's a good overclock. Not very many s754 OCs got past 2.5-2.6 ghz back in the day.