I don't think that board will work with a Tualatin. The board that followed it, the TUSL2 does.

A Tualatin adapter may help, but those are even getting hard to find nowadays.

And those hardware mod pages were fine back in the day when parts were still insanely expensive and you wanted to make a slower, cheaper part perform like a faster one but now unless the part you want is extremely rare, it's better just to buy the real thing. Most of the high end parts from back then are relatively cheap now. No need to risk damaging parts with hardware mods.

Well I only got the CPU for like 6 euro shipped, so that's pretty cheap. Adapters are way too expensive, usually more than 30 bucks.
I'm not going to buy a new motherboard either, unless I really really have to.
I've got the skills to mod the CPU or even the motherboard to accept the Tualatin, I just need to be sure that I've got a tested and working technique.

Heres another guide that is slightly different but worked for a BX board: http://digilander.libero.it/grandecigno/Tua_BX_41.htm

Looks like you just need to remove or insulate the 3 pins for the P3 default voltage then short the other 2. Many sites say this will work. Some will then get the 1012c beta bios to get the voltage adjust to work.

I just bought a CUSL2-CBP (Black Pearl edition) off ebay yesterday. Also had bought a lot of 10 P3-S 1.4GHz (actually got 12 though) with minor bent pins. You have me thinking about trying it.

Looks like the only thing to be careful about is if it boots at 2.05volts then just shut down quickly.

The VTT isn't listed in many places but as far as can find it made some peoples system more stable.

Hello and thanks for that other guide.
I'm kinda confused as to what the mod actually does. Does it force 1.45Voltage on the motherboard when the CPU is connected? The CUSL2 with latest bios has a lowest Voltage Rating of 1.75V and that's what I'm pumping my PIII 1GHz with.

It's a pretty easy mod to do if you've got a steady enough hand for the soldering involved. I've done it before, on a slotket. And the guide linked in the OP is pretty much the same as the mod I did, although I insulated the pins rather than breaking 'em off, and IIRC I put AK4 to AG1 instead to make wiring a little cleaner. (If you don't plan on going over ~1.5V on the VCore, you could even get away with just bending the AK4 pin on the CPU over to touch the adjacent VCC pin at AJ5.)

I also put the wire bridges on the back of the board when I did it. I'm not sure why the guy did it on the socket side in the tutorial you found.

I still don't get it, does the mod force the CPU into running at 1.45V, regardless of what the motherboard's voltage options are?
So I don't need to do anything else other than this simple mod in order to get the CPU to run normally on my CUSL2?

F2bnp wrote:

I still don't get it, does the mod force the CPU into running at 1.45V, regardless of what the motherboard's voltage options are?
So I don't need to do anything else other than this simple mod in order to get the CPU to run normally on my CUSL2?

The problem with Tualatin is, Intel changed a couple pins around so Tualatins wouldn't work on Coppermine boards.
I've recently tested the CUSL2 with a VIA Nehemiah and it worked perfectly fine with the correct 1.4-ish voltage, so voltage itself shouldn't be a problem.

So voltage is fixed, kinda like the multiplier in many CPUs?

I still don't get it, does the mod force the CPU into running at 1.45V, regardless of what the motherboard's voltage options are?

It sets the default boot voltage, I think you can still change the voltage in the BIOS if your board has such options. Though I've never had a PIII board which allowed you to change the voltage manually, so I'm not 100% sure on that.

Here's the Tualatin datasheet, look at page 20. For a chip with a default voltage of 1.45 or 1.475, they already have VID0 and VID1 tied to VSS internally. And since you need VID25mv tied to VSS as well (otherwise you might get >2V at boot on some boards, though the technical reason escapes me), that will give you a 1.45V default with the mod. You can additionally tie VID2 to VSS to give a 1.65V default. I can't remember if insulating VID0 and/or VID1 would do anything...

F2bnp wrote:

So voltage is fixed, kinda like the multiplier in many CPUs?

What I meant to say is, it's not that Tualatin won't work on the CUSL2 because it doesn't support the lower voltage (because it does!), but because Intel on purpose, switched a couple pins around because they knew it wouldn't work anymore in the old Coppermine boards 😉

What the mentioned adapters do is to actually switch those pins back (or perhaps block them altogether) so that the switched pins of the Tualatin won't cause the Coppermine board to not boot anymore.

You can accomplish the same by doing some pin modding, but many find that using an adapter is simply less of a hassle 😉

F2bnp wrote:

So voltage is fixed, kinda like the multiplier in many CPUs?

What I meant to say is, it's not that Tualatin won't work on the CUSL2 because it doesn't support the lower voltage (because it does!), but because Intel on purpose, switched a couple pins around because they knew it wouldn't work anymore in the old Coppermine boards 😉
Edit:What I wrote is a bit confusing. If Intel had NOT changed switched those pins, Tualatins would work in every s370 board that supported it's lower voltage. Not sure what all that AGTL+ stuff is about, but apparently it doesn't really matter for us with regards to messing around with retro hardware 😉

What the mentioned adapters do is to actually switch those pins back (or perhaps block them altogether) so that the switched pins of the Tualatin won't cause the Coppermine board to not boot anymore.

You can accomplish the same by doing some pin modding, but many find that using an adapter is simply less of a hassle 😉

Alright, that settles it. So I should just do the mod and then it should just work!
Thanks guys 😀

It's not that simple though. I found the pins of these plastic CPU's break very easily!!!, if you break the wrong pin, the chip could be dead. And believe me, soldering the pin back is a real feat! (I can barely solder 2 wires together, 🤣).

I'd suggest you ask someone savvy with this for more info.
If noone here knows anything, then I'd suggest asking specifically about pin-modding here: http://classicplatforms.com/forum/index.php It's a bunch of very kind people over there 😉
They know ALL about overclocking, and I'm certain they know a good deal about pin mods also.

My father is extremely skilled with electronics, he has helped me to a few solderings before along with other stuff, so I should be ok!
I'm still not sure whether or not the CUSL2 supports 1.45V though. I found out that it supports early Coppermine Celerons though and these used to run at 1.5V, so it possibly works ? And if it truly supports 1.5V, why isn't it an option on the BIOS ? 😖
Anyway, I'm still waiting for the CPU to arrive, I'll keep you posted guys!

Old Thrashbarg wrote:

It's a pretty easy mod to do if you've got a steady enough hand for the soldering involved. I've done it before, on a slotket. And the guide linked in the OP is pretty much the same as the mod I did, although I insulated the pins rather than breaking 'em off, and IIRC I put AK4 to AG1 instead to make wiring a little cleaner. (If you don't plan on going over ~1.5V on the VCore, you could even get away with just bending the AK4 pin on the CPU over to touch the adjacent VCC pin at AJ5.)

I also put the wire bridges on the back of the board when I did it. I'm not sure why the guy did it on the socket side in the tutorial you found.

What did you use to insulate the pins? Nail polish?

Oh, and I wonder if this mod would work with my Abit VP6. 😈

Nah, nail polish doesn't work very well for that purpose, it scrapes off too easily. I think I may have ended up using superglue.

F2bnp wrote:

My father is extremely skilled with electronics, he has helped me to a few solderings before along with other stuff, so I should be ok!
I'm still not sure whether or not the CUSL2 supports 1.45V though

Mine does.

I'll go look up that thread...

Edit2:Proper link

Old Thrashbarg wrote:

Nah, nail polish doesn't work very well for that purpose, it scrapes off too easily. I think I may have ended up using superglue.

Yeah but we're talking about a ZIF socket here. Just dropping the chip in shouldn't scrape anything off. It's not like the earlier sockets where you had to force the pins into the holes.

Yeah but we're talking about a ZIF socket here. Just dropping the chip in shouldn't scrape anything off.

And what exactly do you think happens when you close the lever on the socket to lock the chip in place? There are still forces involved, and there is still friction between the pins and the contacts in the socket, and nail polish can still get scraped off. I'm not basing this solely on theory here... I've tried it, and it doesn't work very well.