Maybe I just have to give up: no 700@866 anymore

[Karsta]

I am running out of ideas. System is not anymore stable with 124 MHz FSB, CPU 868 with 1.95V, AGP 2x83MHz and PCI 31MHz. I have tried to lower the CPU temp and got it to 37° under load. Still 3D Mark2000 causes crashes when looping - it used to be stable in 38°. Raising voltage to 2.00V didn't help, changing memory or its settings didn't do anything.

Maybe it is the mb after all - it can have difficulties with this power hog GF3 or high AGP bus.

Any ideas would be appreciated!

[dozier768]

how big is your psu? if its under 300 wats that might be the culprit

[Karsta]

It is 230W -I suspected it earlier (then it was temp actually) and bought a crappy 300W PSU. The new 300W gave worse results...

The 230W PSU I'm using can give 125W for 3.3V and 5V (115W for 5V alone) which should be enough. I think CPU (31.3W 868MHz, 1.95V), GF3 (28W), HD (2.75W) and memory (maybe 8-9W) consume together about 70W under load. There is still 45-55W for rest of the computer which is more than enough.

Motherboard can be a little bit different thing though. It possibly can't give all the power needed. But I can't calculate the need (too many unknowns - like: does GF3 use 3.3V only as reference voltage or also for something else). MB gives max about 27W for VIO if I've understood right.

[Dug]

You probably hit one of the walls on your CPU. I have a Cel2 633MHz, my wall was at 100MHz. To jump from 83MHz to 100MHz I had to increase my voltage from 1.85V to 2.3V.

[Endeavor]

if you dont want to keep your 700, ill gladly take it :)

[Karsta]

Yes, I fear that I hit the ceiling. Anyway I can use it at least for everything else than gaming with 868MHz... Or actually if I could get it as it was I can play for an hour or two without problems.

I'm still a bit suspicious about the mb. Problems seem to be related to intensive graphical applications. GF2 was maybe easier for mb to handle. Other possibility is that my HS mods for CPU and northbridge had adverse effect on chipset cooling - that I can't measure.

Anyway high Vcore and temperature sensitivity indicate that 868MHz is edge for this CPU - maybe little over.

[Karsta]

Endeavor (Jul 29, 2001 06:13 p.m.):
if you dont want to keep your 700, ill gladly take it :)

Sorry - I think I'll swallow this defeat and stick with this machine for a while. So much effort I've put in it, has grown it dear for me...

[It_The_Cow]

cA2's rot. The mid-800's are just about tops for these chips

[Karsta]

It_The_Cow (Jul 29, 2001 06:20 p.m.):
cA2's rot. The mid-800's are just about tops for these chips

Seems so. It would be fine if one could search the database by stepping mask! I looked after couple different speed cA2s from the database and found out that it stepping mask is maybe a better indicator of the possible proc speed than rated speed...

[It_The_Cow]

You can. Sort listings by their codes and reference them with Intel's spec sheets. There's a link on the database results page

[Karsta]

I mean getting for example P3s from 550 to 866MHz on same table and sorting them by stepping mask. It might show some interesting patterns between stepping masks. Likewise of course it would be nice to compare some other columns as well.