VIA KT133 worked just fine with Thunderbird B (it's kinda made for that chip), so I don't see why it shouldn't run the C fine also, provided your board can handle the unofficial 133MHz well enough or you underclock its FSB (making your C-chip run slower). If it won't run it, you can do the pencil trick to unlock its multi, but I have some vague memory that multi's above 12x on Thunderbird could be a bit problematic (there were some problems using the pencil trick and changing a Thunderbird 1400C into a Thunderbird 1400B).

I don't think I ever tried overclocking any KT133 boards though, as I always had plenty boards with a real KT133A at hand anyway.

Does your board have an ISA slot by any chance?

Several weeks ago, i've destroyed one Athlon 1000 B cause i forgot the thermal grease. As a replace i've got an Athlon 1333 C with closed L1 bridges. That means, by default you are able to change multi's if the board has the option for.

Now my VIA family is these:
KT133, KT133A, KT333, KT400 and KT400A.

The point is, only the KT133's are time accurate, and my Gigabyte KT133A mainboard has no ISA slot, i've got the last days also a KT133 board, the Abit KT7 (which i have to test soon, maybe it works or not...).
The Abit has one ISA slot, and i thought maybe it's possible to run this cpu with 7.5x133 setting (default 10x133), also to change speed to reduce heat & power output.

Manual for KT7/KT7A:
http://www.motherboards.org/files/manuals/2/kt7a-raid.pdf

What i actually don't know is if it works. A simple test won't damage anything (chip and board) right?!

Edit:
I would prefer running an Athlon on FSB133. The performance to TDP ratio is quite better...

melbar wrote:

Several weeks ago, i've destroyed one Athlon 1000 B cause i forgot the thermal grease. As a replace i've got an Athlon 1333 C wi […]
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Several weeks ago, i've destroyed one Athlon 1000 B cause i forgot the thermal grease. As a replace i've got an Athlon 1333 C with closed L1 bridges. That means, by default you are able to change multi's if the board has the option for.

Now my VIA family is these:
KT133, KT133A, KT333, KT400 and KT400A.

The point is, only the KT133's are time accurate, and my Gigabyte KT133A mainboard has no ISA slot, i've got the last days also a KT133 board, the Abit KT7 (which i have to test soon, maybe it works or not...).
The Abit has one ISA slot, and i thought maybe it's possible to run this cpu with 7.5x133 setting (default 10x133), also to change speed to reduce heat & power output.

Manual for KT7/KT7A:
http://www.motherboards.org/files/manuals/2/kt7a-raid.pdf

What i actually don't know is if it works. A simple test won't damage anything (chip and board) right?!

Edit:
I would prefer running an Athlon on FSB133. The performance to TDP ratio is quite better...

I really can't tell. Whether you can run it safely @133MHz might also depend on how relatively recent your KT133 is (perhaps newer ones will do better, but honestly, I really don't know and wouldn't want you to take unnecessary risks for no good reasons).

Overclocking is always with extra risks, but if it's only a matter of stability (and if your board can run it), I'm pretty sure many boards have extra overclocking features, like raising voltages a little bit (not all boards have this though, but this was kinda common I think with earlier sA boards, I did the same tweaking with my A7V333 I think).

Perhaps someone with a bit more knowledge could chime in?

And yes, those sA's can burn up very easily like that, burned up a Palomino myself once within seconds, because I also forgotten TIM (I did install the CPU HSF though, but this chip was toast as soon as I tried to make it post like that).

You cannot run a KT133 motherboard's cpu at 133mhz. According to all the reviews back in the day they topped out at 112mhz.

I have a Mobile Barton 2400+ running in my KT7-RAID at anything up to 2400mhz with a 100mhz fsb and 24x multiplier. You have to do a cpu socket pinmod
or run 2 wires to a switch to access the higher multipliers. See the following thread for more info.

Abit KT7A and Geforce 6600GT compatibility

What a pity! Would be bad that i can't use FSB133 with this KT7 board.

The manual of KT7/KT7-Raid/KT7A/KT7A-Raid, it's a manual for all 4 variants of these Abit boards, i've linked previous mail, there is at page 40 shown all the users defined setting.
You mean this is valid/available only for the KT133A chipset?

That's right, 133fsb only works on KT133A chipset boards. As I mentioned the only way to get higher multipliers is to mod the cpu socket. I doubt the fsb increase itself
does much for performance as the sdram even at 133mhz becomes a bandwidth restriction at higher cpu speeds. Over 2ghz on the cpu gives barely noticeable
improvements. I don't have a ATI x800 video card, but so far a Radeon 9800xt gives higher benchmark results than a 6800gt.
A motherboard with ddr ram support is what these cpu's need. But I enjoy running hardware on a motherboard that wasn't possible back in the day.