OLD school request: Pentium 4 2.0A northwood BSEL mod?

Seems that google has driven all the relevant information into hiding, since most of what I can find is about bsel modding newer chips.

Does anyone remember or have a link to how to bsel mod a P4 2.0A 400MHz FSB chip to run 533MHz FSB?

I have a complete old system sitting next to me that could use a little extra kick. Why toss it out!

Page 22: http://download.intel.com/design/Pen...s/29864312.pdf

You want to take BSEL0 high (isolate) to get 133MHz QDR (533MHz). That's the pin in grid AD6 on page 43. Note that the diagram is the pins looking through the top of the processor. Carefully count the pins down and over when you flip it in a different orientation.

You can isolate the pin with lacquer or nail polish (let dry completely) or by breaking it off (not recommended). I have used a very tiny piece of masking tape and enlarged the hole in the socket to isolate S370 and S478 pins. It is tricky. I have also had success using plastic from a bag stretched over a flattened needle to make a pin sleeve, But you don't want to get anything stuck inside the socket so proceed with caution.

ah it would seem i fucked up and clipped AD5 and its still 100mhz

then i went back and clipped AD6 and now it hangs on boot lol, crap. anyone wanna give me a free old p4? =p

ah well now it gets funny, I took an old P4M that didnt work on this mobo (2.66ghz) and clipped AD5 now it boots (at 533MHz fsb no less) but only at 1.6ghz.

I fail so hard. At least the machine runs.

sodder it back on

You can take AD5 back low with some conductive paint to any nearby ground (Vss) pin. If you have a fine enough soldering tip and steady hand, you can solder a strand of wire to AD5 and wrap the other end around a nearby ground instead.

I don't suppose you would know why a p4-M 2.66GHz (533 fsb) chip that previously wouldn't even post on this motherboard would suddenly work by cutting out AD5 would you?

I mean, it didn't work yesterday. It didn't work today. It didn't work after I toasted the 2.0A and tried to use it. Then I clipped AD5 and it runs 1.6GHz with 533FSB (and I thought AD5 was the 133MHz BSEL...)

strange...maybe someone knows how I can pin mod the multiplier to something significantly higher

Mobile chips default to the lowest multiplier in virtually all regular desktop boards. There is no multiplier pin mod. You're seeing the lowest 12x muliplier at 133MHz QDR FSB = 1.6GHz. There isn't a reason why it wouldn't have worked before removing BSEL1.

What people usually do is select the highest FSB when putting mobile P4-M chips in desktop boards, usually 800MHz (obviously the board has to support 800MHz FSB). 12x at 200MHz QDR FSB = 2.4GHz.

old board, only supports 533, and for whatever reason it absolutely would not boot up with bsel1 (ad5 i assume?) hot. Too bad on the multipliers...that really bums me.