Depending on if you want real DOS mode sound support versus running through Windows then MB chipset matters. But Athlon64s can run Win98 and are cheap around here, I recommend going Socket 754 for Win98 versus Socket 939. Prices vary by region but I've got MB + CPU + RAM shipped for under $50 USD. Then add in a Geforce 5500FX which run $30-45 USD. Then a Sound Blaster Live or Audigy for audio which run around $20 or so. That ends up getting about $100 but still needing case, psu, and storage.

A great feature of those CPUs is there CPU cooler mounts are still compatible with modern coolers so a brand new AM4+ cooler will work on it just fine and be much quieter than anything stock from that era, and probably provide better cooling.

If you aren't picky about high end stuff and can deal with the few titles that don't run well on fast systems you can make a trouble free Win9x gaming system based on basically any Pentium 4 board that has an Intel chipset, DDR RAM and an AGP slot.
The best thing about them is they all use +12V to create the CPU voltages so you can use basically any modern PSU with 20(+4)pin motherboard connector and 4(+4)pin CPU connector.
Add any SB live! card for sound and any Geforce 3/4/FX GPU plus 256-512MB RAM and virtually any (compatible) P4 CPU and you'll have an enjoyable experience with >90% of Win9x games for still very little money.
Everything beyond that is just for higher performance in late Win9x AAA titles.

I agree about P4 systems being the cheapest way to go.

If Win 98 games are first priority and DOS games are second priority, I'd highly recommend either a P4 or an Athlon 64 with a VIA chipset motherboard. P4s and A64s can be had very cheap, and VIA chipsets have very good driver support for Win 98, and in my experience, the ACPI implementation is very good too (shutdown/restart is reliable, ACPI throttling works very well). I have a preference for A64s due to the CPU multiplier control and compatibility with new heatsinks but P4s are more plentiful due to high production and business use of P4s during their era. DDR ram is dirt cheap. Low end GeForce FX series like 5200 and 5500 are cheap and good enough as long as they are 128-bit memory interface. You didn't mention sound cards but there are a variety of cheap PCI sound cards available with at least decent DOS compatibility. I'm a fan of Yamaha YMF7X4 cards as they are as close to do everything as you can get.

If DOS gaming is a first priority, you're likely going to have to pay some retro tax for a P3 or older socket 462 athlon board with an ISA slot to ensure good DOS sound compatibility. At least thats what people around here say, but I have yet to run into any compatibility issues with my YMF744.

I have a P4 build with an intel 865p chipset. Rock solid stable and great performance. Has SATA 1.5 support that works great with windows 98. USB 2.0. Gigabit ethernet. The works.

An ATI 9600 is a cheap and very fast video card.

The MX 440 or cheaper FX cards are a lot slower but in some ways are more retro friendly. But with a "slower" video card, IMO a P3 board with an ISA slot makes more sense. That way you have the option of installing an ISA sound card for DOS.

"Retro tax", how appropriate to describe the situation. I applaud!

mothergoose729 wrote on 2021-03-05, 18:08:

I have a P4 build with an intel 865p chipset. Rock solid stable and great performance. Has SATA 1.5 support that works great with windows 98. USB 2.0. Gigabit ethernet. The works.

An ATI 9600 is a cheap and very fast video card.

The MX 440 or cheaper FX cards are a lot slower but in some ways are more retro friendly. But with a "slower" video card, IMO a P3 board with an ISA slot makes more sense. That way you have the option of installing an ISA sound card for DOS.

I don't know about the 9600Pro, but with a 9500Pro I quickly noticed some negatives like scrolling on "Lost Vikings" not being smooth (on real dos, on windows 98 it's even worse), I don't think it happens with a geforce MX

but yes, the MX is inferior, still I remember around 2002/2003, GF4 MX + lower clocked P4 being very popular even,
and for most windows 98 games it's kind of a beast anyway (well as long as you don't push resolution to modern levels that is!)

but like most people said, S478, S462, S754 are very 98 friendly and very easy/cheap to find, and something like the famous FX5200/5500 is going to be extremely easy to find and cheap and perform OK (specially with a relatively fast CPU, and a 128bits model)

if you want a p3 with isa slot for example it starts becoming a bit harder, and realistically speaking P3 is kind of slow for some early 2000s games that were still officially supporting 98.

ATI's compatibility with DOS is not as good as Nvidia's. The 9600 pro is very fast and cheap, but it really only makes sense on a fast machine meant for windows D3D games.

Finding a socket 370 or slot 1 board with an ISA slot is not hard at all and they aren't really any more expensive than decent socket 478 boards. I don't think a pentium 3 is a bad match at all for period appropriate games. It really depends on what you are trying to do.

Thank you guys for the replies. Some excellent suggestions here! Clarification: I have a dedicated 486DX machine, so DOS compatibility/support is a non-matter. It's 100% about Win98 and (potentially) some winXP.

I also happen to have a Sound Blaster Live that I salveged from an old PC ages ago. It's still in my drawer and should be working.

I hate them but the cheapest is a old OEM P4 with a dirt cheap Geforce 3/4MX/FX what have you.

Throw in a decent sound card and off to the races, it will play 90% of Win98 games that are worth playing.

Most of us spend more time trying to recreate the bygone days of hardware that we lusted after when new, than actually playing the games we claim to love. At least I know I do....

SScorpio wrote on 2021-03-05, 16:50:

A great feature of those CPUs is there CPU cooler mounts are still compatible with modern coolers so a brand new AM4+ cooler will work on it just fine and be much quieter than anything stock from that era, and probably provide better cooling.

This sounds fantastic, actually. I recall old hardware being really noisy, so this would be really welcome.

Same goes for GPUs. Passively cooled would be my preference, since it also gets rid of the fan problem. I mean, those are 20-year old fans, so they are likely in need to be replaced, which is extra hassle.

The cheapest FX5500 model with a 128-bit memory is this one:

the price is roughly 8$. How's that? good enough?

Retrojanusz wrote on 2021-03-05, 23:10:

This sounds fantastic, actually. I recall old hardware being really noisy, so this would be really welcome. […]
Show full quote

SScorpio wrote on 2021-03-05, 16:50:

A great feature of those CPUs is there CPU cooler mounts are still compatible with modern coolers so a brand new AM4+ cooler will work on it just fine and be much quieter than anything stock from that era, and probably provide better cooling.

This sounds fantastic, actually. I recall old hardware being really noisy, so this would be really welcome.

Same goes for GPUs. Passively cooled would be my preference, since it also gets rid of the fan problem. I mean, those are 20-year old fans, so they are likely in need to be replaced, which is extra hassle.

The cheapest FX5500 model with a 128-bit memory is this one:

the price is roughly 8$. How's that? good enough?

It's 8$ so yeah. If you find you need a faster card later eight dollars feels pretty easy to get rid of.

I would not go below 5700 for FX series.

Just set your expectations appropriately. It is good for 1024x768 resolution, probably not much in the way of AA and AF, and you won't want to play classic XP games like farcry or half life 2 on it. It will tear up quake III and half life though.

The FX 5500 is basically the same as the FX 5200. It is all in the clock speeds. Here is more or less what to expect.

https://www.youtube.com/watch?v=09qvRCv7ThE

slot 1, 440bx boards are still cheap. I don't get the logic that becasue P4 is newer than PIII that its any more reliable. On the contrary a lot of p4 boards were produced during the capacitor plague.

You can do slot 1, 440bx + Geforce 440MX, 256 MB of ram, Spinner hard drive. And a cheap slot 1 cpu. You can probably build that for under 100 dollars including case and PSU, if you find a junker.

My Win98 system is a Pentium 4 without hyperthreading, 512MB RAM, Intel motherboard, SB Live 5.1 and a Geforce 2 MX 400 video card. Yes, the video card is a bottle neck for a lot of things, but that's what I had available and so far, it works correctly for all the games I want to run on it. Lack of ISA slots does not bother me because I have a Pentium MMX 233 system for DOS games that require that.

kolderman wrote on 2021-03-05, 23:17:

I would not go below 5700 for FX series.

IIRC the problem with the FX 5700 is that its an NV36 and thus you can't INF mod it for older driver support. May not be necessary for OP depending on his games but worth bringing up. FX 5800/5900 are ok.

Re: I don't understand all the hate for the Nvidia FX series

GPU - I've been told to look for Geforce 4 or 5, such as 4200Ti, but those are unfortunately plagued by retro tax

Normal GeForce FX 5600 or 5700. Nobody loves these cards. Avoid any FX5200/5500 junk, they are far below GF4 Ti performance.

Retrojanusz wrote on 2021-03-05, 23:10:

The cheapest FX5500 model with a 128-bit memory is this one: […]
Show full quote

The cheapest FX5500 model with a 128-bit memory is this one:

the price is roughly 8$. How's that? good enough?

My 5500 FX is also passively cooled though it has a larger heatsink than that one. For $8 it's worth a try. If you mod the inf file so the 5500 is recognized as a 5200 you can use I believe the 46.x drivers.

Stick with Direct3D 8 or earlier games. The FX cards are Nvidia's first 9 cards but it doesn't run well. For 9 games I use an XP machine.