800E's or 800EB's?
 
Makes a difference. If they are 800E's (100Mhz FSB) then my personal recommendation is the Supermicro P6DBE, a BX based dual Slot 1 board that has been extremely stable for me. No SCSI on mine. Used varying video cards such as V5, V3, TNT2, TNT2 Ultra with 2 V2 12mb in SLI.

I would not suggest a dual processor based on older GX or BX chipsets, there are many reports of problems on these. I had the same question a while back and there were many posts of SMP users having problems(search on SMP and you'll see what I mean). One stood out that had none, Ronin's system, and I am GLAD he posted his specs. He had no problems. He is running on a tyan 2400 board based on the i840 chipset. The tyan 2400 has been phased out and is no longer available so its not one I could go with. I did buy a PIIIDR3 based on his experiences and must say I was not surprised to find that I had little problems with this board as it is also an i840 board. I think you will need to do the research to find out which board you want. I am not sure if the PIII 850s you have are slot1 or fcpga so I wouldn't know which board to look for. Also, you may not want to look at buying expensive RDRAM so this too is a consideration. There are many i840 boards out there with different configurations if you look real hard. I have also heard of some companys selling RDRAM risers that convert to SDRAM. Just be sure its an 840 chipset if you want it to be stable.

EM - they're standard E's. Slot 1, not fcpga. I had been looking at the P6DBE, but wasn't sure if my CPUs were compatible with it, since I think the SuperMicro site only lists CPUs up to 600 as running on that mainboard - could be wrong. Any particular board revision I should aim to get?

I would recomend the gigabyte 6bxd. This board is decently priced and ive been using one since december 99. This is a dual slot 1 board, 5pci, 2isa, 4 ram slots, agp2x, ata33 .. the board itself is fairly basic I guess, but at the price its very good and I have not had any problems with it so far at all. It is very stable. There are bios updates so it can take p3-800, p3-850 and for acpi win2000 compatability and I have run the system with a geforce 2 GTS without any problems.

Here is my getup. Rock Solid! Zero problems with anything. Yes, this is a BX based board and it might cost a little more, but it is incredibly solid. I recently built 5 other machines with mobo only with PIII 800Es. Not a single problem. All using either a GeForce 2 GTS or MX.
 
My two cents worth.
 
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System Specs:
Asus P2B-D
Dual PIII 700MHz
512MB PC100 RAM
Elsa GeForce2 GTS 64MB Video Card
Promise Ultra66 Controller
WD 15.3 GB HDD ATA66 7200 RPM
WD 20.5GB HDD ATA66 7200 RPM
Asus 50x CD-ROM
Sony 4x4x24 CD-RW
SB Live! Platinum
Razor Boomslang 2000 USB Mouse
Wacom 6x9 Intuous Art Tablet
SuperMicro SC-750A Case w/ 400 Watt PS

Many thanks to all the people that replied - having looked into it I've decided on that Asus board. Can't wait to have something that actually works

Hey Dokt,
what were your problems with the tiger 133.? Could you describe them to me? i have recently purchased one and i cant seem to get it to work. i am using a Geforce 2 GTS and it locks to hell whenever i use the video card. It will run fine without drivers installed. but the second i put on any drivers it will lock up to hell sometimes on startup. I am considering calling Tyan and making them exchange the board out. Thank you for your help.
 
Sparkhard

Hi Sparkhard,
The problems you're having are exactly the same as I encountered. I actually review PC graphics cards (amongst other things) for a living and so I have a large collection of them. The only Nvidia card I've ever managed to get running is the Creative GeForce DDR (and believe me, I've tried all drivers right through from 3.81 to the latest 7 series). I get serious freezes when using anything else. I did get a Radeon 32Mb DDR to work satisfactorally, but its performance was less than the Creative card so it didn't solve a lot. My advice is to either change the motherboard (since Tyan show no signs whatsoever of wishing to solve the problems with this board)or perhaps trade in your GeF2 for a Radeon 64Mb DDR. Hope this helps.

Just wanted to thank you guys for the advice. I've bought and installed the Asus P2B-D mobo and it's every bit as stable as you said. Everything installed flawlessly - everything works. Lesson learnt - steer clear of new mobo's and use only tried and tested models.