P5b - Terminal FSB voltage ?

[peonyu]

I just got my new board in, a P5b vanilla board and everything is running great.
There is one item in the Bios that I have had very little luck on figuring out completely -
Terminal FSB in the Jumperless config portion there..

It looks to be Voltage settings for the northbridge and SB chips, but yea, Im not sure. And if it is, Im also not sure on whats safe to set it to.

Right now I have it at auto, and my overclocked settings are 300FSBx10/1.4vcore
.
Im having trouble hitting 3.1ghz. So if this is voltage Im sure it would help..so what are the 'safe-good' settings for this if it is Voltage for the NB/SB ?

 

[n7]

Your vanilla P5B lacks the adjustment for NB/SB voltages; those are available in the P5B-D/Commando, etc. boards

As for FSB Termination voltage, i found it wasn't really necesary to mess with much, though it helped me a bit for higher FSBs, so i usually have always used 1.3v instead of 1.2v

Technical explanation of FSB Termination voltage...
http://www.xtremesystems.org/F...?p=1518741&postcount=7

 

[peonyu]

Ok that makes sense. This board undervolts a hell of a lot [1.425 vcore now] and it goes down to 1.37 at load...I believe that is the problem as my FSB really isnt going to make any records as its at 300 fsb which seems typical, even on a vanilla board.

So time to up the voltage some more!

 

[n7]

300 MHz is nothing in your board.

You should be able to do more.

That said, what are your system specs, all of them?

P5Bs were fantastic mobos for their time, but they are getting long in the tooth these days.

You will have major vdrop & vdroop on them with quads, & if you run 2 GB DIMMs, the lack of manually adjustable tRFC means you'll never get very high clocks for 2 GB modules unless its tRFC in SPD is loose, & AUTO timings are useable.

 

[peonyu]

System specs right now:

P5b Vanilla
E2180 Cpu@3040mhz-1.420Vcore
2GB DDR2 800 @ 900mhz-2.1V
HD4850
Xp120 HS/120mm fan

Psu...which could also be the problem -
Antec 430W Trupower

 

[n7]

You should try dropping down to 1:1 for now.

2:3 is a strong ratio on the P5B; it's great if you have RAM that can do that, but until you determine your CPU's max, you should keep the RAM outta the mix.

So IOW:

10x300 DDR2-600.

Just keep the RAM underclocked till you figure out how far the CPU can go 🙂

I wouldn't really want to go much over 1.45v actual personally, but that's up to you.

 

[peonyu]

I reached 3.3max @ 1.4V-333x10. Turned out that the Ram was choking as you suggested.

The cpu voltage really annoys me, I had no idea that vdroop was a feature till earlier today, and I thought it was my board undervolting. But luckily there was a pencil mod to disable it for the most part [1.4v load via penciling now, vs 1.46 to hit 1.4 load before]. Intel sucks for adding that onto boards....Anyhow, the temp peaks at 65c but a reseat should fix it up, the XP120 didnt seem to need as much pressure on this board as it did the A64 ones, im sure thats the prob there.

Thanks for the help 🙂

 

[n7]

Not bad work 🙂

If you're happy with 3.33 GHz, see what you can do with your RAM.

If you run 5-5-5-15, depending on how good your RAM is, you might be able to do DDR2-1000 (2:3 with 10x333).