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HP Z400/Xeon Workstation to Gaming Desktop build thread...

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Jul 14, 2003
So as a birthday gift to my little brother, who has a PC that is always sub-par and behind, i stumbled upon an ebay deal that seemed pretty good. An LGA1366 Z400 gen2 mobo (6 dimm slots for triple channel), Xeon w3550 (slightly faster version of i7-950), and 6gb of ram for $80. A little research determined i would also need to create a sort of PSU adapter to use a standard ATX psu on the slightly non-standard Z400 mobo (3 pins are different). I did what is shown in this link:


So, before i got started, i ran Firestrike on the current setup. 6gb DDR2 in dual channel, Core2Quad Q6600, Geforce GTX 560. It didnt go well, but heres the physics score which is the important number given that this GPU driven test is only seeing a mobo/ram/processor change.


So i got to work on the swap and discovered a few snags: Documentation on the pinout for power switch, LED, etc is hard to find. The HP documents i found show they used a pre-assembled block, so they didnt have to specify. I found the power switch via trial and error, though still stumped on the others for now. I also had a terrible issue POSTing, even though i got it to POST once (at which point the board told me one stick of ram was bad). Turned out to be a rogue standoff causing a short. At first glance, this standoff looked like it was in the right place, so it kept fooling me for a while. And the the last snag, this mobo uses a 5 pin CPUfan connector. No problem, the first 4 pins can still sense RPMs and stuff so the PWM function of a 4pin fan still seems to work, however without the 5th pin the mobo registers the HSF as a "low power" unit in use on a "high power" CPU and thus throws a "Press F1 to continue" error on bootup. It really isnt that big a deal but I'd like to bypass this still if anyone has any advice.

Here are some pics:







So, a hefty increase in the physics score. On the right track! However, the way i had installed windows 7 and then upgraded to windows 10 and then did this hardware swap prevented me from being able to reactivate windows 10. So im in the midst of a reformat now. Windows 7 is installed and im running the windows 10 media creation tool to upgrade immediately. But then i had to go to work and that was on "checking for updates: 0%" which in the past has taken forever.

But that "press f1" to continue issue is gonna be a bother once the upgrade begins (and possibly going forward, wanting seamless reboots or boot ups). Had to use a stock LGA1366 cooler from a friend while i wait for a Hyper T4 bracket kit to arrive in the mail to re-use the little brother's Hyper T4 on the C2Q board. More to come!
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Starting to feel a little down i cant up his GPU game either...but i cant keep spending money either and ive spotted a few 7970s for around $70-$80 and it just makes me grit my teeth lol. Ahhhhh. Maybe waiting and telling my little bro to save up for an RX480 will be the best way to go, especially for longevity.
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Looks like the 560 is still holding its own. Thanks 1600x900! lol

Please forgive the quality/angle, was awkward to do this without a proper stand.

This setup seems to do better than i thought on RB6:Siege, Bf4, and UE4 Unreal Tournament. Here are some videos. Siege was on LOW, while BF4 and UT played well on medium!

Now, upon further inspection, it seems the RAM is only running at 1066. Im not sure how to get the sticks to run at 1333. They are indeed 1333 sticks but CPU-Z reports they are running 533mhz instead of 666 so im not sure what to make of that. The board is on the newest BIOS and i didnt see any particular settings relating to ram speed, so im not sure.

Update on this: Think ive figured out why the RAM is only running at 1066 at least. The w3550 Xeon only supports a max of 1066mhz RAM, so the RAM is running at the max speed for the processor. I also checked the better Xeons for the socket, like the w3690, and they specify they support 1333mhz RAM, so i think the holdup is what the CPU can support. Will see an improvement in RAM speed in a future upgrade then im sure.

The CPU still heats up more than i'd like with a stock 1366 cooler, i may have put a little too much thermal paste. Either way, im awaiting the bracket still so i can put the Hyper T4 on it and then it should be good to go.
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and im spent!

Cooler brackets arrived, got it installed. Reminded me of how much i hate doing TIM jobs because i feel like i never get it right.

First attempt, i tinned the bottom of the HSF (and thus also filled the crevices between the heatpipes). Applied a small dot to the CPU and installed. Prime95 got into the mid 70s C within a few minutes. I shut it off and pulled the cooler back off.

Second attempt, i tinned the HSF again after cleaning it. Cleaned the CPU too of coruse and applied thin lines of TIM to the center of each heatpipe on the bottom and installed. Initial load temps were 10*C less but over an hour of running Prime95 the highest temp i saw was on one core only, at 69*C. All the other cores were a little less (maybe 1 or 2 or 3 degrees less). This im fine with, im running out of thermal paste anyways. Clean it up and let my little brother know his present is ready. The board didnt come with an I/O shield, which was expected. So i sorta made my own. Hopefully it lasts!






Now, i know overclocking (possibly with a different cooler down the line) will be limited due to being on OEM board. Though some research online, ive seen inklings that a few different people got software overclocking working but not a whole lot of details. One guy said he got intel XTU working to OC it, though i thought it didnt support 1366. Maybe an old version of XTU? Another guy said he did it with SetFSB, though i saw another tried SetFSB and said it didnt work. And then another program called ClockGen exists but i couldn't find results of OCing with this, and i need to find the board's PLL for the clock generator (i think) to try it. Maybe some other crafty Z400 "repurposers" will find this thread and give those programs a shot and chime in. For now, im happy with this setup (minus the graphics card, but i knew that going in. Its still performing admirably, however.)

One additional question here for you all. This computer will be for general use/Gaming. What CPU should i have my brother keep an eye out for in the future?

Quad-Core hyperthreading x5687 that runs at 3.6ghz/3.9ghz (highest frequency CPU available for the socket), or hexacore beast CPU w3690 that is 3.5ghz/3.7ghz (the highest rated CPU for the socket). Again, when it comes to gaming, which one is the better CPU? Benchmarks (passmark specifically) rank the w3690 way higher than the x5687 so theres that.

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i have the Z400 myself right now i have a xeon w3565 in there but i hear the w3690 is the best u can get plus it has an unlocked multi and they can be had for under 180 on ebay i saw one yesterday for 125 on ebay keep me posted on the overclocking im interested in that my self
not sure never tried it i use my z400 for gaming i have a xeon w3565 15 gigs ecc ram and a 750ti gpu so far the only game i have issues with is the witcher 3

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also keep in mind that they make a special liquid cooling cpu cooler for the z400 i use it to cool my cpu and man what a difference it makes
Can you measure voltage from the 5th pin to ground?

pin 5 is a ground from the diagram i was looking at. Either way, i dont have the computer anymore so i couldn't help you sorry.

not sure never tried it i use my z400 for gaming i have a xeon w3565 15 gigs ecc ram and a 750ti gpu so far the only game i have issues with is the witcher 3

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also keep in mind that they make a special liquid cooling cpu cooler for the z400 i use it to cool my cpu and man what a difference it makes

It definitely has the capability to be a good gaming machine with the PSU adapter to power a bigger GPU. Water cooling isn't necessary, the 775 cooler my brother had fit just fine and does the job well enough. I imagine any normal 1366 cooler will do a good job too. I have heard of HP's all in one water cooler though. Interesting.
Build update: My little brother managed to scrounge enough money for me to find him a decent GPU, but didn't have a whole lot of options with a sub-$140 budget still.

Fortunately i still managed to snag a used Gigabyte Windforce III Geforce GTX 770 4gb graphics card for $129! Should be arriving tomorrow. Also, budget will soon be opening up to pump up this computer enough to be ridden off into the sunset. Those upgrades/accessory items will include a x5687 cpu (4c/8t 3.6ghz base/3.9ghz turbo), 12gb ram to fit his theme (3x Avexir Core 8gb sticks with the green LEDs), 3x Cougar green LED 120mm fans, and finally a window case mod. The mod would probably look something like this:

Looking forward to getting this build "there."
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Graphics card is in and 3dmark score is updated. Yeah buddy!



Before Score:

After Score:

Some quick tests in RB6: Siege and Bf4 proved fruitful. Both games running 60fps on high or very high with vsync on, no problem. Everything was on low to run well previously so FPS improvement wast too huge (thanks to vsync) but the quality change is huge and that was the goal. Theres a smidgen of coil whine on this card from turning vsync off but bf4 hangs around the 90-110ish FPS easy. Didn't try Siege with vsync off. Input lag doesn't feel much different with it on, so on it stays! (and no barely audible buzzing or coil whine this way too).
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Its almost done! Hardware-wise, its complete. Aesthetics? Waiting on getting the panel cut to mod a window onto it.

-x5687 Xeon installed
-Avexir CORE Green LED 12gb DDR3 1600 in triple channel installed (only runs at 1333 because thats all the CPU supports though)
-Apevia AF512L-SGN 5 pack of green LED fans
-Airgoo RGB controllable LED strip

Here are more pics. Razer eat your heart out lol.






Benchmarks with that crazy processor (~$70 on ebay) were pretty good too. 1000pt increase (to 8868) in Firestrike physics over the w3550 it had previously.


Cinebench R15 scores

Geekbench 4
Geekbench 4.jpg

and finally, a broader CPU comparison chart i put together

x5687 cpu comparison.jpg

Not bad at all! Seems to beat an FX-8350 and sorta hang in there with last gen i5s.
So...modding a window onto the panel didn't go as planned. Turned out there was a little money in the budget for a new case. I've determined that, after my own experience with this as well, the best budget case out there is the Deepcool Dukase v2. Its $50, sometimes less depending on sales or anything. I have the black one for myself and my brother liked the white one. The case swap went off without a hitch and man, it came out great. This is pretty much the end of the line for this build short of an upcoming wifi card, aesthetic backplate for the GPU (from v1tech), and eventually a 1tb SSD.







Another video i did for my channel on this build.
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The previous case pictured, the black Corsair Carbide 400r, has found new life after a reinvigorated side panel window mod.

I picked up a z400 from ebay for $40, and it came with a W3550 3.06 GHz processor and the motherboard plate w/IO shield. I also picked up 6 sticks of 2GB PC3-10600E DDR3-1333MHz ECC memory for $60. I have some ideas for dealing with the proprietary connectors and sense pin challenges, so I'll post my solutions here. I'll be making my build this weekend with parts I've recently purchased, so I'll be sure to post some pics for the build.

IMG_0507 (1).jpg
sense pin issues are easy! Im on my second build and transplanting. For the PSU, the adapter made out of an ATX12v extension is a must, but forking it off into two molex connectors isnt necessary. You can just solder together or "quick splice" (look up the connector) the specified wires to 12v and ground (i think thats what it needed, double check the pinouts). The USB sense pin you need to jump is on the yellow usb header specified in this thread (this thread will also help you out with solving the sense pin issues in general):

And the rear fan header needs a PWM fan on it to bypass its sense pin (though it really isnt a sense pin, the mobo just wants a PWM fan there). Those 3 things are the key to making this usable in any ATX case. Dont try to use the stock z400 PSU (if you even got one) in a standard size atx case with a PSU basement. It wont fit, its too tall. This i know because i cut and hacked a case to make one fit when i realized it wasnt going to lol. Once you get through those three things, the mobo might still throw "press f1 to boot" errors at you and list which devices it isnt sensing. Anything after the aforementioned 3 can just be disabled in BIOS (like the 1394 header), and the system then boot like normal.

Just finished the build last night...

z400 gama.jpg
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