I have a revision F board that supports dual 850s quite easily. Unfortunately, the memory bandwidth has been halved for some stupid reason.

I try not to delve too deep in to forum gossip about what will work and what won't. From my experience, 50% of the time the accounts of things working do not in fact work stably. In my opinion, the best approach is to try it yourself. You can probe the CPU's Vcc with a multi-meter. As far as how much current is being output, you'll need a multi-meter that can handle 20A, but you'll need to cut a trace, so I wouldn't recommend measuing the current. You can look at the specification sheet for the regulator on the motherboard to see what the max output current is. For anything AC, probe it with a scope. For this test, I recommend sourcing some 700, 850, and 1000 MHz Slot 1 CPUs. If you take your time, you can find them cheaply enough.

For my dual slot 1 board, the BIOS revisions mention the max supported CPU is 800 MHz, however I've been using 850 MHz for many years without issue. While the 1 GHz seemed to initially work fine, after a few hours I'd get errors on the screen every so often. When putting the 850's back, the errors went away. For those guys who claim the 1 GHz CPUs worked fine, they did not mention the extent to which they had tested them. Were they long term stable in an everyday use machine on 24/7? Again, best to do your own experimentation.

Chewhacca wrote:

I have a revision F board that supports dual 850s quite easily. Unfortunately, the memory bandwidth has been halved for some stupid reason.

I can sum up the reason, there is no direct connection between each cpu except through the fsb and when one cpu decides that it wants to snoop the L2 cache on the other cpu before seeking data from the ram it has to do so through the fsb resulting in a bandwidth penalty. It wasn't to horrible early on but in the last days of 771 the bandwidth was very terrible when two quad core xeons were installed. 775 wasn't much better in many ways.

You're talking about Slot 1 Pentium 3 systems yeah?

You have to scroll down to find it, but according to this chart from Tyan, the Tiger 100 supports up to an 850mhz P-III, but with BIOS revision F and higher only. I guess they enable support for the higher multiplier in that revision.

http://www.tyan.com/archive/support/html/cpu_ … ii_celeron.html

Chewhacca wrote:

You're talking about Slot 1 Pentium 3 systems yeah?

Applies to all smp and multi core machines up till 939 and socket 1366.

There are other boards besides the Tyan Tiger 100 which support dual Slot 1 Coppermine CPUs. I have a Dell Precision Workstation 410 motherboard which has been running dual PIII-850 CPUs for years. As I noted previously, 1 GHz caused infrequent cause memory errors after a few hours of use. This was noted with a revision A05 motherboard. I also have a revision A06 motherboard that I'd like to test with the 1 GHz CPUs as well.

There is a Dell Precision Workstation 410 motherboard on eBay now, but it is revision A00, which was a board in production when the PII 400/450's were out (late 1998), so I'm not sure how well it will handle the lower voltage of the PIII Coppermine CPUs.

There are always those PowerLeap Tualatin converters for dual slot 1 server boards. They were about $150 per adapter in 2002/2003, but I got mine FOC for evaluation. PowerLeap had quality issues with their China-produced fans on these units, which would stop turning after about 5 days, causing the system to hang, but other than that, they should work fine if you find a fan which will continue spinning given the very close spacing between CPUs. I ended up getting rid of those adapers in favour of using a dual socket 370 board. I'd like to find a 440BX board which works with the off-the-shelf 1 GHz 1000/100 CPUs just for the novelty of it, but for the time being, I'm content with dual 850's.

I'm not sure what the latest revision of the Dell Precision Workstation 410 is.