The MSI one would be my pick, with some solid reviews from back in the day. But the PC-Chips board is actually really interesting. If it works and is stable I'd want to try it out, it's a really late Socket A board with a interesting sis chipset.

It depends...

Does the MSI K7T Turbo2 have an ISA slot populated? On google search i see versions with or without ISA.
So in case it's there and you want also a good DOS compatible PC then i would take this board.

If you have an Athlon with 133Mhz or 166Mhz FSB, then i would go for the other KT333 MSI.

Only in case you want to run the 200Mhz FSB, then i would take the Biostar.

The VIA boards are the most compatible with Windows 9x when it comes to sound in DOS games. The SiS board as well, I think. If you can replace the noisy northbridge fan on the KT3, that would be my choice.

But if you're going to run Windows XP... Can you check if the southbridge has MCP-T written on it? nVidia SoundStorm is interesting when it comes to features/performance. And yes, dual channel DDR400. Moreover you can slam every AthlonXP in that socket.

My choice would be Biostar M7NCDU due to: having both PATA (for boot disk) and SATA (for storage), dual channel memory (for slight performance boost), AGP 8x support. It's a late board so you can plug any Athlon XP into it. Try to pair it with Nvidia 7xxx graphics card or at least 6xxx. I personally have a couple of Socket A boards - 2x nforce2 400 ultra and 1x KT600.

MSI K3T ultra - VIA KT333 - I would avoid this one. KT333 has only AGP 4x, doesn't support DDR 400 without overclocking AGP and I wouldn't be sure about AMD Barton compatibility. I would avoid KT333 unless you get it for peanuts.

Pc Chips M848A v5.0. I would avoid anything from PC Chips for Athlons.

MSI K7T Turbo2 - VIA KT133A with bad caps - if it has ISA I would buy it if it's for peanuts. Otherwise it's worthless.

For Athlons you want either KT133A if it has ISA or KT400A/KT600/nforce2 ultra (ideally one with SATA).

First of all: win 98 and DOS compatibility are nice, but I'm aiming at win XP here. I've already got 10+ win 98 pcs running.

Alexz mentioned about AGP 4x on the KT3 versus the AGP 8x on the Biostar, does tell me the Biostar should be a little faster.

DDR 400 support is great, and maybe this can be set async to the 333 bus of the Athlon XP 2800. Otherwise there's no win in getting DDR 400 speed capability.

The K7T uses SDRAM and thus would be slower. I can imagine it also has AGP 4x at max, so again a bit slower than the Biostar. And it lacks ISA.

The pc chips board is a weird thing. Theoretically it should be able to be a winner, but with pc chips you never know.
E.g: I've got a M577 super 7 boards that's rock stable but is slower than you'd expect.

I guess I'm going to set up both the pc chips and Biostar and see which is faster.

Now I know these boards all rely on the 5v rail. I've got some older quality PSUs that can provide around 22-25A (fsp, delta) and I'm a bit worried about the power drain.

I'm guessing for 5v:
- Athlon XP 2800: 65W = 13A
- mobo: 2A
- 2x HDD, FDD, 2x odd: 5A
- two random PCI cards: 2A
- graphics: ATI Radeon 9800 pro: ??A

The Radeon has its own molex connector, may this one rely on the 12v rail or is it basically a 5v cards? How much current would this drain from the 5v rail?

Alternatively I could use the Nvidia 6600, which has no external power connector. How much would this one drain?

1.) Ok, as you have already enough w98 alternatives ready, you don't need any boards with ISA slot.

So you can exclude the slowest board with KT133A chipset.

2.) Regarding the power supply, i would advise you to use PSU's with at least 30A or higher on the 5V rail.
Do not underestimate the power draw of the Athlon in combination with a high end card (Geforce Fx , Geforce 6 ...)

3.) About the RAM speed. For this athlon architecture, an synchronized frequency is best for performance (FSB166 - DDR333 and FSB200 - DDR400)

4.) About the difference AGP4x to AGP8x , for the following pictures, there you have several benchmarks which i have found at different comparisons.
(Including a comparison of SIS746FX vs. NForce2 vs. KT400)

test setup:
Gainward Geforce4 Ti 4600 (128 MB DDR-RAM)
Athlon C 1200 MHz
Asus A7V133

--> benchmarks with different settings for 'Graphics Aperture Size'

VGA cards:
Geforce 4 Ti 4200 64Mb (NV25)
vs.
Geforce 4 Ti 4200-8X 128Mb (NV28)

And here you have some results with SIS746FX chipset...

You want two Socket A boards probably anyway the 2nd being a backup. But given the poor benchmark results for SiS 746FX I doubt the Pc Chips board would be a good choice.

AGP 8x may be useful for the top end AGP graphics cards and games which can utilize lot of memory and need frequent data transfers. DDR 400 support is mostly to keep options open in the future in case you find an Athlon XP 3000+/3200+ cheap. The justification of aiming specifically for late Socket A boards is virtually nonexistent price difference.

If you plan to run winXP go with the nForce board (the biostar). Pair it with the 6600 or 9800 and 1 gb of ram and done. For 98 go with the MSI KT333 board.

Ok, so the pc chips and K7T are out of the run due to their inferior performance.

That leaves the KT3 and Biostar in the race.
Performance should be a little better on the Biostar as I look at the figures from Melbar, so I'll set up that one first.

And as Alexz suggests: keeping a second board is not a bad idea and I'll keep the KT3 as a spare. The benefit of being able to run a 200MHz fsb CPU is now not important, but maybe in the future... Who knows 😀

And ofc the power supply: I already figured there's going to be a slight chance my PSUs won't cut it, so I'll look into that. I actually have a 30A PSU but it's the sketchy noname type, so I didn't mention it. And won't try it, I'm not that much into magic smoke 😀
I'll see if there's accidentally something in my pile of more modern stuff that gives me some more juice. Or go see if there's something nice for sale 😀

Back to the pile of PSUs. I've found one that seems to have a good chance:

Codegen 300xx

12v does 10A, +5v does 30A and it even has -5v (even while I don't need the latter one)
Has good weight, seems to have all components in place and I've read more good reviews on codegen here.

It was hidden in a pile of more modern stuff, due to its P4 connector. 😜

###

I'm ready to build my Athlon XP machine!

Time for some compressed air. Looks solid!

My PIII rig uses PSU with 3.3V 20A, 5V 30A, 12V 13A rating.
Socket A is going to use 20A, 30A, 14A 350W PSU.
For Socket 754 I have one with 20A, 16A, 10A+13A 350W.

I've got two Socket A rigs for parts that both used wrong PSUs - modern ones with weak 5V rail. In both cases the original owners underclocked the CPU to 1.1Ghz. One had only 12A on 5V, the other one 16A.

300W PSU on that picture is intended for Socket A systems or older.

I've got an old 300W PSU with bulged capacitors (needs repair) that makes hissing noises and it has 3.3V 28A, 5V 30A, 12V 15A. Very unusual to have 3.3V rail that strong.

Yeah, I've separated the dust from the rest and it's turned my walkway a bit grey :p

Any way, there's a little more clear to me about this setup and power usage:

- Athlon XP 2800: 65W = 13A
- Biostar M7NCDU: 2A (?)
- HDD1: Seagate Barracuda 80GB: 0,8A
- HDD2: WD blue 250GB (2,5"): 0,55A
- FDD: less than 1A
- DVD drive : 1,3A
- graphics: ATI Radeon 9800 pro: 5A

About 24A, with a 30A PSU, should be safe. I still can add another odd or a few PCI cards.

I don't need FireWire or extra USB. The motherboard provides 4 usb2 ports.

The system boots, but there's another thing.
The 5v rail drops to 4,80v AMD the 12v rail rises to 12,86v (multimeter reading). The 12v is a bit too high to be comfortable to me. So I guess the PSU is near it's limit here...

When I plug in a nice little geforce mx4000 the 5v rail is still at 5,02v and 12v rail at 12,34v. 🙁

So I'm going to have to choose a slower card ...
In the AGP box available:
- fx5500
- fx 6200
- fx5200
- Radeon 9600
- Radeon 9250
- Ti 4200 (2 actually)
- quite some Mx series and early AGP cards

And I can't find my fx6600 somehow -_-

@Alexz:
The 30A for the Pentium 3 is a bit overkill, but if it works fine, there's no harm in it 😉

Indeed the socket A platform can be hard on the 5v rail, just as I've experienced now.

I do have a modern 500W PSU that can provide 25A on the 5v rail, but I guess it will be too low as well for this 65W CPU.

Socket A was a bit in between technologies: the 5v rail was on its max and the 12v rail was slowly taking over. With s754 motherboards were more relying on the 12v rail, just as Pentium 4 did. Fortunately. 😜

I'm using a Ultra X-CONNECT with my son's socket A system and it's been rock stable since we built it 3 years ago and he uses that system alot. If you can find one get it and you won't be disappointed.

It seems there are actually Socket A boards that are designed for modern PSUs. I have a few such boards:

MSI KT6V (20pin + 4pin power connector) - manual specifically states the 4pin 12V connector is used to power the CPU
Epox EP-8RDA3+
Epox EP-8RDA3I (no SATA here)
Gigabyte GA-7N400 Pro2

All of them are late boards either nforce 2 ultra 400 or KT600 and have SATA.

From my Socket A boards only my old Epox EP-8K5A2+ (KT333) doesn't support 4pin 12V connector. It seems Biostar was saving cost by not redesigning the board.

I know there are socket A boards with the 12v P4 connector. Actually the Kt7 is such one. But with SDRAM I consider it a slow board and not ideal for my "fast socket A system".

Besides, I've read some stories these still have great dependency on a strong 5v rail, and the power for the CPU is not always delivered by the 12v rail (which does not make sense, then why add the P4 connector)

Any way: there's an Enermax 600W PSU on its way, which can provide 34A on the 5v rail. Should be strong enough 😀