Wouldn't be surprised if your limited to a pair of Katmai 600's
Both my dual P2 era motherboards were. (Asus P2-DS and Compaq Prolient 1600)

Build quality of these OEM workstation's is on another level, I also get a kick out of gaming on what would have been stupid expensive enterprise level hardware.
I'm liking your hardware choices so far. What OS were you thinking? I went with Win2k which I found actually does a real good job covering for Win98, with only a few games that weren't compatible.

chinny22 wrote on 2025-08-11, 00:47:

Wouldn't be surprised if your limited to a pair of Katmai 600's Both my dual P2 era motherboards were. (Asus P2-DS and Compaq Pr […]
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Wouldn't be surprised if your limited to a pair of Katmai 600's
Both my dual P2 era motherboards were. (Asus P2-DS and Compaq Prolient 1600)

Build quality of these OEM workstation's is on another level, I also get a kick out of gaming on what would have been stupid expensive enterprise level hardware.
I'm liking your hardware choices so far. What OS were you thinking? I went with Win2k which I found actually does a real good job covering for Win98, with only a few games that weren't compatible.

Ahh that's possible. Guess we'll find out when it gets here - I've seen so much mixed info on BX-series CPU compatibility. Dual 600s is still a lot of extra horsepower compared to the single 500 in my XPS T500.

The build quality is a big reason I'm a workstation guy. My last four modern desktops and last two laptops have all been Dell Precision workstations. There is no going back after you've tasted hot-swappable fans and tool-less everything.
I'll definitely go with Windows 2000, that's what I've got on my XPS T500 and my Compaq Armada E700. I've had my share of NT 4.0, W2k is just a nice place to be. I like streaming my Windows Media Player library across the network from my file server to my Windows 2000 rigs while I'm writing or messing around in Bryce 3D.

It was the computer to have back around 1998
The XW was the Top of the line Kayak
I had the XAs and XU versions.
The XW came with a High end video card and Dual pentiums.

I upgraded my Kayaks with Dual Pentium III 500mhz.
They served me well as home office computers.
Very reliable.
I ran Win NT 4.0 and Win2000
I used them until the release of WinXP

The only thing I did not like was that the fans are loud.

Update #1:
The Kayak arrived this Monday. It's in really good condition besides a few scuffs and such. Took it apart far enough to get it cleaned up and it seems to work fine.
As it arrived, the specs were:
Dual Pentium II 400s
512MB of RAM
Matrox G200 8MB
3COM 10BASE-1000 NIC
Adaptec SCSI Controller

Right now, the upgrades I've done/plan to do next week are:
Swapping the fans out for Noctuas
Upgrading the GPU to a Radeon 9700 Pro 128MB
Swapping in my Audigy 2ZS
Adding a PCI SATA Controller
Adding two 256GB SSDs in RAID (mirrored, I forget which level that is)
I bumped it up to 1GB of RAM after I found some PC100-322-620R in a drawer.

I'll post another update and better photos when I get that all done next week. It's currently in about 14 pieces.

Are you sure its slot 1? A XW is slot 2 Xeons, the XU is slot 1.

As promised, here's the "end-of-build" update post. I had meant to make this a long time ago, but I've been busy graduating so better late than never.

As of December 2025, here's the specs:

CPU: Dual Slot 1 Intel Pentium II 400s/512kB
RAM: 512MB
GPU: ATI Radeon 9700 Pro 128MB
Sound: Creative Soundblaster Audigy 2ZS
Display: Dual Dell 1908FP LCDs, 1280x1024
Storage: 256GB Samsung 860EVO SATA SSD via Promise Technologies PCI SATA controller
Network: 3COM 3C996B 10BASE-1000 Gigabit Ethernet
OS: Windows 2000 Professional SP4 with Legacy Update
I replaced all the fans with Noctua units and it's fairly quiet now. Haven't pulled the PSU apart to replace that one yet.

Overall, I'm really happy with this build. It's had a permanent spot in my room since I finished it in August, and it's been enjoying a nice retirement. It makes for a great jukebox, streaming across the network from my NAS or one of the excellent internet radio stations I've found (shoutout SomaFM).
Software wise, I've got Winamp, Photoshop 6.0, Bryce 3D 4.0, Unreal Tournament '99, a 3rd-party Discord client, SimCity 2000 & 3000, and a number of other things. I've been using it to sync with my HP 660LX palmtop, and I ventured into some vintage homelab tomfoolery to get a Windows 2000 Advanced Server VM hosting a VPN so that my friend's XP rig and the Kayak can do Netmeeting and LAN games without any port fowarding on their end (and I am aware of the security risks involved with that, it's all firewalled and on its own VLAN).

Ultimately, I would like to upgrade to dual PIII 600s, but finding the correct VRMs and heatsinks is no easy feat. I'd also like to bump it up to 1GB of RAM but I think I need fully-buffered DIMMs for that.
I would also like to have the missing bezel that goes around the front audio jacks. If anyone's got one they'd be willing to loan me so that I can make a 3D model and print a replacement, please let me know!

ionstorm66 wrote on 2025-10-05, 17:18:

Are you sure its slot 1? A XW is slot 2 Xeons, the XU is slot 1.

Yes. HP did make Kayak XWs with Slot 2 Xeons, but this is just a standard Slot 1 motherboard.

Makes for a very power hungry jukebox!
Not that I can talk, I was using its younger brother, a dual S771 HP XW8600 with a pair of Radeon 4890's for the exact same reason few years ago.
It did mean I didn't have to have the heating on in the room either, so I was saving money in my mind 😉

It is a very nice setup and good luck on those final last parts, at least you can enjoy it now while still looking around

flux1270 wrote on 2025-12-04, 20:07:

Ultimately, I would like to upgrade to dual PIII 600s, but finding the correct VRMs and heatsinks is no easy feat. I'd also like to bump it up to 1GB of RAM but I think I need fully-buffered DIMMs for that.
I would also like to have the missing bezel that goes around the front audio jacks. If anyone's got one they'd be willing to loan me so that I can make a 3D model and print a replacement, please let me know!

Are you sure the GX chipset requires buffered for 1 GiB? I run 1 GiB unbuffered/unregistered on a BX chipset (Asus P2B-DS) no issues (all though it's out of spec)

And VRMs? If Katmai core PIIIs, I'd guess they use same voltage as your PIIs? Or will they need to be capable of more current for PIIIs?

Love these HP workstations.
They are so reliable.
Engineered to run 24/7/365 days a year.

Once my motherboard went bad after a lighting storm
hit a nearby transformer and caused a power surge.
I called HP and they sent me out a NEW replacement motherboard ASAP no questions asked.
These HP Kayaks had great customer service support.

I have been using HP workstations ever since.

Today I use power surge protectors on all my electrical outlets.

H3nrik V! wrote on 2025-12-05, 06:07:

Are you sure the GX chipset requires buffered for 1 GiB? I run 1 GiB unbuffered/unregistered on a BX chipset (Asus P2B-DS) no issues (all though it's out of spec)

I tried two different sets of compatible RAM to get it up to a gig. It would display all four DIMMs on the front panel diagnostics but not in the BIOS and would crash trying to boot into Windows. Went back to 512MB and the problems stopped.

And VRMs? If Katmai core PIIIs, I'd guess they use same voltage as your PIIs? Or will they need to be capable of more current for PIIIs?

The service manual lists only one part number for VRMs across all the CPUs, but also implies that VRMs were included with the CPU upgrade kits from HP. The official text from page 8 reads "Dual Processor Kits include: processor, voltage regulator module and heatsink. Each VRM is specific to the processor with which it was supplied, and should only be used with that processor." Which is confusing as there is only one listed P/N for VRMs.

I've also already run into issues with SECC-1 vs SECC-2 CPUs and heatsinks in my previous Slot 1 ventures so that's a big deterrent for me in upgrading the CPUs.

I once owned a Compaq Prolent where I had to upgrade the VRM's
According to the documentation the original were only good for P2 450 and below. P/N 327563-001 Rev 02 or Spare# 327660-001
The replacement VRM's were P/N320226-001 Rev A aka Spare# 329267-001

No idea if they would work in a HP Kayak though.

Make sure to have the latest BIOs installed before you upgrade the CPUs.
Not doing so I fried a pair of 700 MHuz CPUs on my Netserver once.
The VRMs usually never caused any trouble. Just make sure theyre not from the previous PPro generation.

I found the same Kayak few month s ago and have a spare board fitted to a Vectra XU case.
Did yours have the onboard adaptec SCSI or the NCR add on card?
You may need someone to prit the proprietara Floppy knob, seems missing on yours.

eisapc wrote on 2025-12-08, 14:25:

Did yours have the onboard adaptec SCSI or the NCR add on card?

Mine has the onboard Adaptec controller and came with an PCI Adaptec SCSI RAID controller card as well.

I can model and print the floppy eject button myself, just need someone to loan me a reference (or maybe dimension one for me?).

Only tangentially related to the build, but I found these awesome advertisements for the Kayak line. These are from the October and November 1998 issues of PC Magazine.

I'm trying to clean these up in Photoshop, and then I'm going to get them printed as posters to go with my Kayak setup. I thought they were pretty cool.