how come????

How come my chip when I first fired it up in my kt400 I had my fsb set at 266 because I thought my 2600/333 was a 2600/266 (lucky me) I booted with a 16.5x mult and a 266 fsb but when I put my fsb to 333 because my chip wasn't being recognized right I can't boot above the factory default of 12.5x .

Depends what you mean when you say you cant get higher. FSB or multi. For the multi you cant up it because you only have access to the multis 12.5 and lower on that chip - this is because the last bridge on the L3 is closed I think.

First, your sig "I'm not afraid to make a keychain to get what I want" is way way cool.

Second, need some more info.

1) <simple math> 16.5 *133 = 2194, while 12.5 * 166 = 2075, and 13 * 166 = 2158.

NOTE that your chip 2600/333, stock speed is the 2075.

2) When you up the FSB to 166, and you can't boot at 13, you actually DO have the higher multis available, right? Its not that you are only stuck with 12.5 as the only option?

3) Which motherboard do you have?

4) OC Dectective, some of the KT400 give access to all the multis, regardless of the default from the L3. I'm guessing he must have one of these mobos, because at 133 FSB he could get 16.5, if the mobo went off the L3, he shouldn't have 16.5 at any FSB.

5) It is ?possible? that your chip just isn't too stable much beyond stock.

6) CAN you up the FSB, at the 12.5 multi? For example, can you run FSB = 175 with the 12.5?

7) also drop us your other specs, what speed ram, etc.

good luck!

As far as I know (according to the sticky at the top of this forum) the XP2600 333 does not have access to multis above 12.5 by default so I cant see how he booted at 16.5 even with a KT400(perhaps he mistakenly thought it was at that multi but it reverted to default when booting)?
Edit more info in this thread
http://forum.oc-forums.com/vb/showthread.php?threadid=147406

OC Detective said:

As far as I know (according to the sticky at the top of this forum) the XP2600 333 does not have access to multis above 12.5 by default so I cant see how he booted at 16.5 even with a KT400(perhaps he mistakenly thought it was at that multi but it reverted to default when booting)?
Edit more info in this thread
http://forum.oc-forums.com/vb/showthread.php?threadid=147406

Click to expand...

1) OK, the L3 determines the DEFAULT multi ranges, either (A) below 12.5 or (B) above 12.5.

2) The L1 bridges determine if a set multi in the range is locked. Pallys used the L1 to lock, the tbreds don't.

3) 1+2 mean that ANY motherboard that allows multi adjustments will allow all multis in the range. In other words, a KT266A motherboard should allow all multis from 5.5 to 12.5 for the XP2600/333, as the the 2600/333 defaults to the lower multis, and the KT266A (and most other motherboards) can see all these lower multis.

3A) PEOPLE GET FOOLED into thinking the KT400 unlocks the tbred. It doesn't, as in (2) the L1 are unlocked for all tbreds. The aparent, pretend lock happens when you have TWO conditions met, first a motherboard that does not recognize the higher multis, and second a higher multi chip. In this case, the CHIP IS UNLOCKED, but for multis 13 and higher, and the motherboard only recognizes multis up to 12.5 or 13, so the motherboard and chip SEEM locked, but they are not.

In this case (e.g.2400XP and KT266A chipset) some people will modify the L3 so the chip default is under12.5, and then have all multis 5.5 to 12.5. OR, you can get a motherboard that can see either the upper 13 to 16+ AND the 5.5 to 12.5 multi ranges, like the KT400.


4) KEY IS, SOME of the KT400 motherboards basically BYPASS THE L3, and will give you access to all multis, from 5.5 to 16+. For these motherboards, you get BOTH the low and high multi sets. So it is very possible that pctuner has a KT400 motherboard that would give both a 12.5 AND a boot up at 16.5.

none1 said:

4) KEY IS, SOME of the KT400 motherboards basically BYPASS THE L3, and will give you access to all multis, from 5.5 to 16+. For these motherboards, you get BOTH the low and high multi sets. So it is very possible that pctuner has a KT400 motherboard that would give both a 12.5 AND a boot up at 16.5.

Click to expand...

I havent heard of a KT400 board that can do this - which ones can and where did you hear this?

I messed up when I posted I wasn't thinking, my machine for the first time posted with a 133 fsb default at 12.5x not 16.5x so it was saying it was a 2100xp I had a brain fart. I can't get higher than 12.5 mults but I can post with a 178 fsb... I'm thinking of hardcoding my chip to be a 2700 and cut the last L3 bridge I know some people think thats taboo around here but I am already so close to the highest fsb at this time on my soyo kt400 that a higher mult won't hurt till the muskin pc3500 comes in and I can run 400fsb then I can reconnect the last L3 bridge or by a barton with 400fsb capability already, or go liquid cooling theres enough choices to justify it 12.5 is just to low...

Thanks for clearing that up! I didnt think the multis above 12.5 were available........
You can do a mod that will give you a specific multiplier but I am not sure if you can unlock all of the multis though on a XP2600 333

This thread tells you how to do it!

http://forum.oc-forums.com/vb/showthread.php?threadid=149477&highlight=2600

OC Detective said:

I havent heard of a KT400 board that can do this - which ones can and where did you hear this?

Click to expand...

Abit can, asus can, epox can, MSI CAN'T. Pop in a 2400, get multis from 5.5 to over 16. Did a bunch of research on this when the kt400 first came out, and there were "rumors" of KT400 unlocking the tbreds. Basically, some of the KT400 don't unlock the multi, they just ignore the L3, the tbreds are already multi unlocked.