Klamath 233, I had running at 66 x 2. So yes, worth getting.

I think a Celeron 233 would have no advantage? at least on my board I can disable the l2 cache and the result is exactly the same as the Celeron at the same clock
having the l2 there gives you the flexibility to enable if you need some extra perf.

Totempole wrote:

I'm able to achieve 233MHz by lowering the FSB on the board down to 66MHz. I've never attempted anything like this before and wanted to confirm whether or not it would be advisable/acceptable to do this. Also, how close would the performance be to that of an actual Klamath 233MHz?

That is fine. It will perform pretty much identical to the mentioned Klamath core, but it will run cooler.
Klamath was known to run hot. All Klamath core processors have a flexible multiplier, whereas only early model Deschute core processors have an adjustable multiplier.

And if you have an LX board, there are some that could do 50MHz FSB (dunno about BX's which can lower their FSB below 66MHz from top of my head) which along with x2 CPU multiplier will give you 100MHz.

PhilsComputerLab wrote:

Klamath 233, I had running at 66 x 2. So yes, worth getting.

So it's fine to run the 350MHz Deschutes at 66x3.5 then? Just wanted to be sure.

Should definitely also try to get my hands on a 233 or 266 Klamath then. 😀

Tetrium wrote:

And if you have an LX board, there are some that could do 50MHz FSB (dunno about BX's which can lower their FSB below 66MHz from top of my head) which along with x2 CPU multiplier will give you 100MHz.

It's a BX and the multiplier doesn't go below 3.5x. So even a 233MHz Klamath can't run below 233MHz. 🙁

Are you talking about the GA-6BXC in your signature? It has hardware jumpers and therefor supports every possible multiplier that a Pentium 2/3 can understand. (I have two of these boards myself.)

Weren't all PII-350s multiplier locked?

Some 333s and some 400s were also unlocked though, mostly downwards.
I don't know if there's any Klamaths that are locked, but the less speedy Deschutes have a better chance of at least being unlocked downward.

Tetrium wrote:

Weren't all PII-350s multiplier locked?

Could be. But since there were a few unlocked 400MHz models, I would imagine a few 350MHz ones like that could exist as well. Much better chance for a 333MHz model to be unlocked though.

Edit: know that I typed up my reply when only your first sentence was visible.

gerwin wrote:

Are you talking about the GA-6BXC in your signature? It has hardware jumpers and therefor supports every possible multiplier that a Pentium 2/3 can understand. (I have two of these boards myself.)

Nope, that's one of my many earlier builds. 🤣

The only 2 boards I have available right now are an Intel SE-440BX-2 which doesn't seem to have anything by way of CPU jumper settings, and a Transcend TS-ABX which is what I'm using right now.

Tetrium wrote:

Weren't all PII-350s multiplier locked?

Some 333s and some 400s were also unlocked though, mostly downwards.
I don't know if there's any Klamaths that are locked, but the less speedy Deschutes have a better chance of at least being unlocked downward.

Not really sure about the multiplier lock. I've only tried lowering the FSB down to 66MHz and it seems to work.

You can set 66 mhz fsb on the seattle ii with cpufsb (or cpucool) from windows 9x and of course stays that way in ms-dos mode. However those tools are shareware and you can't save settings, not much of a problem though.
May be other tools support the board's pll but i don't think so.

Totempole wrote:

... a Transcend TS-ABX which is what I'm using right now.

Seems like a winner in that regard:
http://www.anandtech.com/show/328

A DIP switch bank on the board controls multiplier settings

Been testing it out for a while now. Not as slow as I had hoped, but getting there.

Can anyone suggest a good CPU slowdown utility in order to get a smooth result?

The best one I've tried so far is Throttle, but it's far from perfect.

Throttle is already the best one. And yes, it still ain't smooth with some games. (reached: vogons' skill level 'adept')

If you want to go to the next real level of slowness, you need a Pentium II produced before week 34 1998 and lower the multiplier with the DIP switch bank of your Transcend TS-ABX (vogons' skill level 'advanced'). Or get a VIA C3 Processor on a proper slot adapter (vogons' skill level 'madness!').

gerwin wrote:

Throttle is already the best one. And yes, it still ain't smooth with some games. (achievement: vogons skill level 'adept')

If you want to go to the next real level of slowness, you need a Pentium II produced before week 34 1998 and lower the multiplier with the DIP switch bank of your Transcend TS-ABX (achievement: vogons skill level 'advanced'). Or get a VIA C3 Processor on a proper slot adapter (achievement: vogons skill level 'madness').

Disabling the L2 cache in the BIOS got it exactly where I needed it to be. 😀

Strange, L2 cache usually does not make much difference in games. Disabling L1, on the other hand, makes the CPU go to a crawl.
PS. You can use SetMul to disable/enable the L2 without going to the BIOS.

gerwin wrote:

Strange, L2 cache usually does not make much difference in games. Disabling L1, on the other hand, makes the CPU go to a crawl.
PS. You can use SetMul to disable/enable the L2 without going to the BIOS.

I disabled the "External Cache" in the BIOS. I left the "Internal Cache" enabled. I assume that means I disabled the L2 cache.

I can safely say my CPU speed dropped by atleast 1/3 after doing so. It's running at about the same speed as a Pentium 200MMX, even slower than a Pentium Pro.

Totempole wrote:

I can safely say my CPU speed dropped by atleast 1/3 after doing so. It's running at about the same speed as a Pentium 200MMX, even slower than a Pentium Pro.

I suppose. Looking back, PC player bench becomes 33% slower without L2, but Quake 1 just 15% slower:
133 MHz Challenge - 5th/6th gen CPU per clock performance