Running 133 MHz coppermine at 100MHz

[om@dist.unige.i]

Hello, I'd like to upgrade my PC with a PIII CPU and I have to decide if I want to try 133 MHz or not. The MB is an ASUS P3BF that, although not designed for 133, is said to work fine at the speed. I'm not sure about the Video Card though (Matrox Marvel 400) and so I'd like to know if, in case the system won't work at 133MHz, it is possible to make it run at 100MHz.
....
Ok, I know this is a bit off topic for the overclocker forum, however, I cannot think of a better place ;)

Cheers

Mauro Migliardi

[Placid]

If your motherboard allows manual setting the cpu frequency (fsb) to 100 then yes but if its a 133mhz cpu you will be running lower than the cpu's rated speed.

[The Doors]

Hi om@dist.unige.i, wellcome to the Forum,
If I remember well, your Mobo can handle Fsb of 133Mhz and more even if the i440BX is rated for up to 100Mhz, I'll try to check the Mobo manual to give you a complete answer ;)

[The Doors]

Yes, your Mobo can works with Fsb up to 150Mhz or 140, 133, 124...setting properly the Dip-Switch (DSW-Switches) check page 18 of the user manual.
With a chipset cooler with fan on the North Bridge (the big chip near the slot1 socket), a good Cpu cooler & a good case airflow you can handle high Fsb freq. without probs.
Another possible way is to use a P/// 850E 100Mhz and OC it rising the Fsb @133Mhz ore more for a great Overclock @1133Mhz!

I hope it helps you ;)

[Treker]

If your board has a 1/4 pci devider I wouldnt worry to much about 133mhz fsb, given that your mother has an option for these fsb speeds, you should'nt have a problem getting to 133fsb besides the usuals such as heat..

I would however look for a p3 chip with a higher muiltipler and fsb of 100mhz.. that is if you want more room to overclock and still stay near specs!

I'm would be interested to see how this goes, keep us posted m8!

-Trek

[JaY_III]

Originally posted by om@dist.unige.i
Hello, I'd like to upgrade my PC with a PIII CPU and I have to decide if I want to try 133 MHz or not. The MB is an ASUS P3BF that, although not designed for 133, is said to work fine at the speed. I'm not sure about the Video Card though (Matrox Marvel 400) and so I'd like to know if, in case the system won't work at 133MHz, it is possible to make it run at 100MHz.
....
Ok, I know this is a bit off topic for the overclocker forum, however, I cannot think of a better place ;)

Cheers

Mauro Migliardi

So you want to know if you AGP card will do 100MHz.
You can find out right now in your current computer.
What you do is change the AGP divider to 1/1. (i asume you have a 100FSB system right now) And PRESTO, instant knoldge of what your AGP will be able to do.

[Phil]

Setting a 1:1 divider is one way for sure of finding out if the agp card will be ok at a 133mhz fsb, but if it isn't stable at 1:1 that doesn't mean it won't manage an 89mhz agp bus when the system is at 133mhz. I would say it's a fair bet the card will be good at that speed, I have seen a g200 marvel run fine at an 83mhz fsb but I would try something similar to what jay said but at a lower fsb. Of course you need to be sure your ram is ok at 133mhz as well

[GuNRocK]

asus boards are pritty good....i am an amd person myself but i have an oldskool Celeron333A with asus P2L97 it only supports 60/66bus but i was able to get 75.5 and 83.3 to work great...it would have supported 100mhz bus but my board was only designed for pentium II cpus 233~333mhz so there were no 100mhz cpus out at the time....but yours is newer it hsould support 133.....i though 440BX boards had the ability of doing 66/100/133 buss speeds 133 not officially supportd

[Phil]

Most bx boards can manage a 133mhz fsb quite easily with the odd exception (the bp6 for example) the issue here is if his vid card will and I would say it's a fair bet it will. But do test to be sure.

[AmbientFiction]

Yes but if your wanting to OC don't get an EB(133mhz) CPU get yourself a 100mhz and OC the ever loveing core out of it. Other wise you might be very un happy with what you get out of that EB CPU

[vimal]

I have a P3B-F. If you use the BIOS to set FSB (instead of using the DIP switches) you'll see that up to 124MHz FSB has 1/3 divider, while above 124MHz have 1/4 divider. (actually, there are 2 124MHz settings, one with 1/3 and one with 1/4) This means that your video cards (and all other peripherals) will be running completely in spec with a 133FSB - no need to downclock to 100FSB. Just make sure your ram can handle 133FSB as well.

[Placid]

While the pci bus will stay in spec. the agp bus on a bx chipset only offers a 1/1 or 2/3 agp bus setting.


Originally posted by vimal
I have a P3B-F. If you use the BIOS to set FSB (instead of using the DIP switches) you'll see that up to 124MHz FSB has 1/3 divider, while above 124MHz have 1/4 divider. (actually, there are 2 124MHz settings, one with 1/3 and one with 1/4) This means that your video cards (and all other peripherals) will be running completely in spec with a 133FSB - no need to downclock to 100FSB. Just make sure your ram can handle 133FSB as well.

[om@dist.unige.i]

Thanks to everyone guys for your help, however I cannot do any testing right now because I'm currently in US and the PC I'd like to upgrade is back home in Italy. I just wanted to see if I can get a good bargain on a not-top-notch-anymore PIII (e.g. 600-750) and drop it straight into the MB to replace the current C333A
The memory is 133 so it should do, the MB (from what you say and what I have read ;) should work fine. The only unknown remains the V-card but I cannot do as Phil and Jay suggested (set the AGP to 100MHz) because I don't have the PC with me.
Wait! Even if I had it with a Celeron the FSB is 66MHz so I would not be able to do such a test would I?

Anyway, I feel I have a better grasp of what I will have to face now and I will definitely let you know how it will end... a month from now ;)

Cheers and thanks again

[Phil]

Well I recomend you get your self a 100mhz fsb chip and plan on overclocking it to a 133mhz fsb, that way the very worse that can happen is you run at stock but it is likely that you would be able to manage a 133mhz fsb.

[The Doors]

I absolutly agree with you Phil,
for me the best chips to go are the P/// 850E or a P/// 1Ghz always with 100Mhz Fsb.