Hardcoding multiplier?

[hassmh]

I've got a 1.3 Duron that I want to play with the multiplier, but the board doesn't have multiplier adjustments. If I wanted to hardcode the multiplier to 10x, what would I need to do? I've got the pin mod done, so I get 5x now, but whatever I do to the L1s doesn't have any effect. This is my first unlocking, so any help would be most appreciated.

[Kamerat]

The German site OverClocked inside (http://www.ocinside.de/index_e.html) have guides that show you witch bridges you need to open and close to hardcode the multiplier. You must use the guide for XP's bacause you got a Morgan Duron.

[hassmh]

Ok, so I have to mess with the L3 and L4 bridges too, I guess. Looks like a PITA. What would be the best way to cut those tiny little bridges?

[snvpa]

exacto knife works well for me. make sure you use a magnifying glass too

[Gravity Man]

I was unsuccessful cutting bridges with a knife. Remember that Durons use a ceramic substrate, which makes their bridges very difficult to cut. I was going to try a dremel cut-off wheel, but the motherboard I intended to use with my duron died in a heatsink mounting accident before I was able to try with the dremel.

[John C.]

Originally posted by hassmh
Ok, so I have to mess with the L3 and L4 bridges too, I guess. Looks like a PITA. What would be the best way to cut those tiny little bridges?

Home-made tool. Get from your dentist the finest pointed diamond coated rotary burr, with the very smallest conical angle at the tip. Then epoxy it into an appropriate tube for use like a surgical instrument or pencil. Cut ceramic and bridge/s with finger motion like writing number "ones" crosswise the bridges. if your dentist won't oblige, ours did, then try hdwe or hobby shops, but the keys are "diamond coated" and "very fine tip" 'cause the bridges are not very long and you just want to cut them, not obliterate themin case you want to close them again.
Ceramic is like butter to this tool, so check progress often.
John C.
PS If your dentist won't give you a used one, he's real cheap, they only cost 3 to 4 $$ each. And never use power tools, they skip around on the surface, make a mess.

[hassmh]

Hmm, yeah I've tried a variety of knives, nothing seems to do very well, even my extra sharp ceramic knife. I'll have to look into the diamond coated thing. My dentist is pretty cool, he might be generous :D Too bad he's closed next week. By then I'll probably have gotten through them with one of my knives!

[hassmh]

I DID IT! :D I found somewhere the idea of blowing the bridges with electricity! Wired up a pushpin to ground on one HDD molex and one to 5V on another, bridged 14 and 15 on the ATX connector and fried them bridges. Worked like a charm, much faster than grinding away with a knife. While I was at it I blew the L10 so I wouldn't need the pin mod which is a PITA to clean off if I ever wanted to go back to stock.

Anyway, up and running at just over stock, 10x133, will push the FSB a little more later. When I get a new fan I might be able to hit my goal of 1500.

Thanks for the help on my first unlocking! Next one will be a Palomino XP, so it will be a little different.

[The Coolest]

Congrats on the successful unlock, and good luck :)

[hooziewhatsit]

Originally posted by hassmh
I DID IT! :D I found somewhere the idea of blowing the bridges with electricity! Wired up a pushpin to ground on one HDD molex and one to 5V on another, bridged 14 and 15 on the ATX connector and fried them bridges. Worked like a charm, much faster than grinding away with a knife. While I was at it I blew the L10 so I wouldn't need the pin mod which is a PITA to clean off if I ever wanted to go back to stock.


Where did you find that idea? I'm interested in how exactly you did it.

[Gravity Man]

I think I read about it somewhere on the front page a while back...

[hassmh]

I don't remember which thread it was, some other thread about unlocking a 1.3 Duron, someone metioned frying the bridges. I did just what I said before, but here's some more detail:

Pin 14 of ATX connector is the power on pin, Pin 15 is a ground pin, so connecting the two (or 14 with any other ground pin) with a little wire starts the power supply.

All the grounds and 5Vs on all the connectors are electrically the same, so I used two different HDD molexs for the 5V and ground to give myself a little more manuverability.

I got two 2-3" pieces of insulated wire with both ends stripped. Stuck one end of one in a ground pin of a molex (actually made a U and stuck it in so it would stay) and did the same with the other wire in the 5V of another molex. Made a loop with the other ends and stuck pushpins through them.

Put the ground pushpin on one dot of the bridge to be blown, then carefully put the 5V pushpin on the opposite dot and ZAP! The tiny little bridge can't handle the current and frys. There's still conductor left so the bridges can be reconnected if needed.

Note that you could do this with a PS from a running computer without having to short the ATX connector pins, but I think that would be a little dangerous. If you like playing with electricity (I'm an electrical engineer, so it was a no-brainer for me :D) this is the way to go about it.

[Mazon]

You can also change your multipliers at the bottom side of the processor by connecting the right pins. For example 1800+'s multiplier is 11.5 --> "wiretrick" to pins AL27 and Vcc_core, and the multiplier will change to 12.5.... Awesome?

[John C.]

Originally posted by Mazon
You can also change your multipliers at the bottom side of the processor by connecting the right pins. For example 1800+'s multiplier is 11.5 --> "wiretrick" to pins AL27 and Vcc_core, and the multiplier will change to 12.5.... Awesome?

But safe practice should always install a current limiting resistor when tapping into a voltage supply like Vcc_core, to protect the power source in case of short circuits. Not easy to do and esp risky when working with "loose wires" as in the "wiretrick"...unless one makes soldered connections to the sockets on back side of mobo...in which case then easy to add the current limiting resistor.

Always best to "understand" what particular mods do, like the suggested mod changes the 1X Bit Value from Disabled/LO to Enabled/HI.
http://www.beachlink.com/candjac/index.htm link to Signal Circuits article to see signal circuits diagram and recommended current limiting resistors. Then also Multiplier Code article explains AMD's Multiplier Code.

For the interested.
John C.
Edit:- Additional reason to avoid "wiretricks" to Vcc_core....Palomino's unlocked/Open L1s...instant short circuit if "wiretricking" a signal circuit whose L1 has been grounded to sub-surface ground plane in pit during the L1 closing mod...a quite common mod failure.

[Mazon]

I was referring to this picture. If you cut connections from L3 bridges, you will not need additional resistor. But, if you close extra L3 bridges, you must use 1 Kohm resistor. Correct me, if I am wrong.

edit: Uups, that is for tbred's

[hassmh]

That's why I blew the bridges, I think it's easier than messing around under the CPU. I had previously tried connecting two pins under the CPU to enable the 5-12.5 multipliers, and that was a pain. Since I had to blow some bridges to wire in a different multiplier, I just blew the L10 while I was at it to enable the lower ones. MUCH easier, but not for the faint of heart. Kinda scared me for a second on the first one seeing something go POP on my proc. But the rest were fun :D

[John C.]

Originally posted by Mazon
I was referring to this picture. If you cut connections from L3 bridges, you will not need additional resistor. But, if you close extra L3 bridges, you must use 1 Kohm resistor. Correct me, if I am wrong.

edit: Uups, that is for tbred's

First off...ita's/fab51 picture shows the AMD design circuit, and you "can cut or close L3 bridges without any additional resistors" because that particular "internal" Vcc_core voltage supply/connection in the picture is most probably protected by current limiting "pullup" resistor/s not shown in the "Internal Pullup Circuit" box.

Second, yes the pic is Tbred with factory closed L1s, which shouldn't cause any grounding problems like the manual closing of Palomino's open L1s could. But could still ground elsewhere with "wiretrick" mod on a Tbred or any other CPU. So never a good idea to "just pick up a voltage supply from a socket pin without protecting it with a resistor".... which is what the "wiretrick does.
John C.