As alluded to in my previous post about the Dell Wyse 5070 thin client, the days of cheap Raspberry Pis are over, so it’s time to look at cost-effective and reliable alternatives. The 5070 was a good indication that refurbished thin clients were a very viable alternative, with that specific model being quite like a slightly weak, but otherwise ordinary PC. I think the 5070 is pretty good for most small-server uses, but it wasn’t perfect. When something gets too popular, prices start going up too.
As a result, I think it’s good to have alternatives, so when UN Tech decided to sell a batch of HP t640 thin clients for practically the same price as a 5070 (~AU$70 including postage and GST), I thought it was good to see what the alternative had to offer. The price was hard to pass-up, as this particular unit is still on sale for around AU$1000 new. On paper, this unit has more CPU and GPU performance with an AMD Ryzen Embedded R1505G, but how would this translate into power consumption and suitability for the small home server role? After all, these boxes were originally designed to run HP’s ThinPro, Microsoft Windows 10 IoT Enterprise or IGEL, rather than some consumer OS. Also, how does it fare regarding upgradability, which is one of the 5070’s main limitations. This post will show my journey commissioning a very versatile HP t640 Thin Client to join my fleet.
The Unit
The HP t640 is a fairly pretty unit, only slightly larger than the Dell Wyse 5070, but with a rounded shape. The front of the unit is home to the power button, a USB 3.x 5Gbit/s A port, a USB 3.x 10Gbit/s A port, a USB 3.x 10Gbit/s C-port and a TRRS combination jack for a headset.
The rear of the unit has three DisplayPort dual-mode ports, each supporting 4k/60Hz. There are two USB 2.0 ports (great for a keyboard and mouse), a TRRS combo jack for a headset, a gigabit Ethernet port, two USB 3.x A ports and an option USB-C port supporting DisplayPort out. There is also a small power input jack and a Kensington lock slot.
The sides of the unit have a diagonal stripe design which aids in ventilation.
Ventilation slots are straight on the top and bottom. The base itself has a large rubber base to keep it in place on the desk.
Two relatively thin thumbscrews are used to secure the base to the main unit.
The unit was provided with a relatively small power adapter, roughly the size you might expect with a netbook.
The power adapter is rated at 19.5V at 2.31A for 45W. This unit was manufactured by Chicony Power Technology (Chongqing) and carries an efficiency mark VI. The plug has an aqua-teal coloured insulator.
Under the Covers
This unit is filled with covers – for example, this cover which hides a lot of details.
The Windows holographic label suggests this unit formerly ran Windows 10 IoT Enterprise. The details of the unit are printed on the metal plate inside.
There is a sort of mounting plate inside.
Opening up the unit can be achieved without tools. There is a catch which can be released by hand to remove the plastic rear fascia. Pressing on the green release tab above the USB and audio jacks …
… and unclipping the top lid side clips allows the top lid to be removed. There is a metal grid pattern, likely to maximise airflow while keeping radio noise containted. There is a special feature in the form of a protrusion which connects to a thermal pad on a shielding can over the RAM for additional heatsinking.
The main unit has a motherboard which is somewhat smaller than the case, with a number of mezzanine boards connected by ribbons and cables. It’s a rather complex sandwich of boards. It also has a pretty nice heatsink at the left connected by a heatpipe. Because of the curve of the casing, even the Wi-Fi E-key slot is at an angle.
Looking closer at the main storage slot, the 2230 eMMC has a label over the eMMC chip itself. But the printing on the motherboard tells us this slot is compatible with M.2 SATA or NVMe/PCIe/eMMC. That’s a very valuable finding as it means modern SSDs can be used along with their performance benefits.
To remove the eMMC card, you’ll need a T8 Torx screwdriver to remove the retainer. The back of the eMMC card seems to suggest this is “MOTHIM Rev: A” with a HP Part Number of L42743-001. There is a copyright date of 2019 and a PCB manufacturing date code of Week 13 of 2021. Other names seem to include “TRANQUIL-6050A3055001-NEWCARD-A01(A1)”. The main chip appears to be a BH720FJ1LN PCle to eMMC5.0 HS200 bridge with a date code of Week 11 of 2021.
Two Samsung 4GB DDR4 3200MHz SODIMMs can be found under the shielding can, along with a thermal pad for improved heat dissipation (but only for the top SODIMM).
This unit comes with a USB-C DP output option card pre-installed. This card seems to be built around an Analogix SlimPort ANX7440 retimer/mux chip.
A Few Hurdles
As this box is not a mainstream consumer PC, there were some interesting hurdles when it came to testing and preparing the box for use.
Installing Windows
For those who would like to install Windows, my t640 certainly put up a few fights. While it was supported under Windows 10 IoT Enterprise edition …
… when trying to install Windows 10 (consumer retail edition), the installer seems to get stuck in a loop booting up and eventually times out with a BSOD indicating DRIVER_PNP_WATCHDOG. This suggests some default included driver in Windows 10 was not happy and ended up getting stuck – something I last experienced back in the Windows 9x days. Perhaps an older or different version of Windows 10 install media would boot, but I didn’t attempt to debug this.
Installation of Windows 11 was a little more smooth, with the installer managing to boot successfully, but then, we got stuck at the point of choosing a destination drive.
There were no drives to choose from. This is because this unit, in spite of having Windows in the past, utilises an eMMC storage device of HP’s own design. The default included drivers can’t talk to it.
An easy way out, although a costly one (in the sense of needing hardware) is to replace the eMMC entirely with a SATA M.2 or an NVMe M.2 SSD. These would be detected automatically and should also offer better performance.
It is at this point, I should say that Linux scores an absolute win here, with Ubuntu 24.04 LTS not having any complaints whatsoever, detecting the eMMC right away.
I was curious to see how the eMMC was implemented and Linux helped me work it out. Based on the lspci output, it seems an O2 Micro Inc. PCIe reader with VID 1217 and PID 8620 is being used to interface with the eMMC.
01:00.0 SD Host controller [0805]: O2 Micro, Inc. Device [1217:8620]
(rev 01) (prog-if 01)
Subsystem: O2 Micro, Inc. Device [1217:0002]
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
ParErr- Stepping- SERR+ FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast
>TAbort- SERR-
Kernel driver in use: sdhci-pci
Kernel modules: sdhci_pci
Digging a little deeper, I discover that this is a BayHubTech device codenamed “Seabird”. Not thinking straight, I decided to download a driver supporting this PID/VID pair from another OEM and try preparing it for Windows 11 install to load.
The driver was identified (bhtpcrdr.inf) and loaded, but …
… no drives appeared. Well, it turns out this was entirely my fault for choosing a random driver because it turns out that driver was coded as a card reader device for removable media (i.e. the way the chipset would have been implemented in many laptops).
Instead, doing what I should have done and going to HP’s downloads page, I could download the driver they used with Windows 10 IoT Enterprise which is in Softpaq sp111380.exe. Once that is run and extracted, we get this 7-zip self-extracting archive.
Extracting the files, we have the correct driver (bhtemmcdr.inf).
Putting these onto a USB stick …
… now, the eMMC is detected. Ignore the other partitions and mess – it’ll become clear why they exist if you read the upgrades section towards the end of the post.
But this also means that the HP eMMC module used in the t640 isn’t anything but a PCIe x1 card-reader chip and an eMMC glued together on the one M.2 2230 board. As a result, this eMMC could be used in any PCIe x1 capable slot on any machine, in theory. I suspect this approach was taken because the M-key socket used for the storage is only capable of handling PCIe x4 and SATA, thus there is no native ability to carry SDIO like the E-key socket would. Using a lower-end socket would limit performance for higher storage options. Making this an E-key card and taking up the Wi-Fi socket would cause problems for some configurations. By doing it this way, they can avoid relying on the host SoC to have an SDIO controller of the right level of performance and ensure it is a more universal storage option (provided BIOS support to boot from and OS drivers to make it run) even if it’s a little more expensive than a bare eMMC. It’s probably still cheaper than a full-fledged M.2 SATA or NVMe SSD.
BIOS Update
My unit shipped with BIOS v1.08 which is quite out-of-date. HP also keeps maintenance on the BIOS of these units, currently at v1.21. However, updating them is nowhere near as easy as working on the 5070.
For one, downloading the Softpaq sp152017.exe and executing it extracts a bunch of files. From there, there’s an HTML guide that isn’t that useful for those who don’t want to flash from within an OS. I thought I could grab the M43_0121.bin file, stuff it on a flash drive and ask the BIOS to update itself. Unfortunately, getting into the BIOS using F10 and then choosing the update option merely resulted in the insistence that the “file is missing or damaged”.
Another annoying BIOS quirk was the F12 boot menu which was mostly useless …
… as it never seemed to list any boot devices like USB keys or the like which needed configuration in the Boot Order menu of the full BIOS. So much for convenience – the Dell BIOS is much more to my liking in this regard.
Soldiering on, I learned that there was an executable tool inside the Softpaq’s extracted folders under the Win folder called M43_0121.exe that could generate a USB bootable recovery drive. Unfortunately, running this under Windows 11 just results in a stuck executable – no amount of compatibility options meddling could get it to work.
The only way was to run it on a Windows 10 box which then managed to generate me a recovery drive.
But alas, going back into the BIOS and trying to update still failed. This time, it was because the tool itself was being stupid. I used a 64GB flash drive which was exFAT formatted. Instead of reformatting it as a large FAT32 drive, it retained the exFAT format and I believe the BIOS just couldn’t handle this.
I copied the whole file tree as it appears below:
+---HP
+---BIOS
| +---Current
| | M43_0121.bin
| |
| +---New
| | M43_0121.bin
| |
| \---Previous
\---BIOSUpdate
BiosMgmt.efi
BiosMgmt.s09
BiosMgmt.s12
BiosMgmt.s14
BiosMgmt32.efi
BiosMgmt32.s09
BiosMgmt32.s12
BiosMgmt32.s14
CryptRSA.efi
CryptRSA32.efi
HpBiosMgmt.efi
HpBiosMgmt.s09
HpBiosMgmt.s12
HpBiosMgmt.s14
HpBiosMgmt32.efi
HpBiosMgmt32.s09
HpBiosMgmt32.s12
HpBiosMgmt32.s14
HpBiosUpdate.efi
HpBiosUpdate.s09
HpBiosUpdate.s12
HpBiosUpdate.s14
HpBiosUpdate.sig
HpBiosUpdate32.efi
HpBiosUpdate32.s09
HpBiosUpdate32.s12
HpBiosUpdate32.s14
HpBiosUpdate32.sig
I then got Rufus, formatted the drive as large FAT32 and then shoved the same files back onto the USB key. Entering the BIOS using F10 and requesting the BIOS upgrade option …
… I finally managed to update the BIOS. This was more work than most, but we got there in the end. This process was rather slow, taking about three minutes or so. This is confirmed with the CPU-Z tool running under Windows – the BIOS update was successful.
Other AMD Drivers
Another difference with the 5070 which seemed to have all its drivers just installed through Windows Update, the peripherals on this board weren’t all ready-to-go after an install.
One of the sound devices and SMBus devices had no drivers. Thankfully, going to AMD’s Drivers page and choosing the R1000 embedded series drivers page provides these two downloads.
Installing these resolved the issues and updated the drivers from the older builds distributed via Windows Update. The Catalyst driver is quite the large download, however.
eMMC Booting
During testing, I encountered three instances where I powered on the thin client and it just sat hung at the BIOS screen. I think it was most likely because the eMMC module had somehow errored or the flash was somehow busy. A hard reboot managed to bring it back into the OS, but if this happens often, it could cause some grief on a headless remote box that manages an unexpected power outage and reboot.
So far, it’s still a very sporadic occurrence, but perhaps it’s another excuse to eliminate the eMMC in favour of something else (although I do note that many ordinary SSDs do have longer time-to-ready after unexpected powerdown due to flash mapping table recovery routines which can occasionally interfere with booting).
Features and Testing
This section will detail some of the features of the unit and testing that was performed.
USB-C PD Power
This unit is very lucky to have come with a USB-C DisplayPort option pre-installed, as this port on the rear also accepts USB-C PD power. Replacing the included 45W power brick with an Anker PowerPort III 65W adapter proved to be trouble-free, with the Fnirsi FNB58 even being able to sit in-line to monitor power consumption. This was definitely a good find, but sorry to say that the standard front USB-C port is not capable of this feat.
Unfortunately, as this is an option module, not all t640s will have this feature. For those that do, this would be great for removing reliance on proprietary power supplies and can even let the unit run from some power banks (although, using a laptop is probably much more sensible than a thin client with a power bank).
CPU & Performance
As promised, the unit has an R1505G CPU with two cores and four threads in a FP5 BGA package. The unit shipped with v1.08 BIOS – this image was taken before the BIOS update.
Included RAM runs in dual-channel mode at 2400MHz, 1T. The modules come from Samsung and pretty much identical to those in the 5070.
Graphics is taken care of by the integrated AMD Radeon Vega 3. Looking at the CPU benchmark scores, it too seems similar to an A10-7850K APU, but a tiny bit faster. Definitely ahead of the 5070 here.
The WinRAR benchmark scores 3214kB/s which is quite a bit faster than the 2637kB/s of the 5070 (+21.9%).
The 7-zip compression benchmark shows a scaling of 323% indicating a benefit from their “hyperthreading” analogue, achieving a compression speed of 9038kB/s and a decompression speed of 161077kB/s. This is a 12.1% and 13.3% improvement over the 5070 respectively, which is not as impressive. The final score was 12.328GIPS, a 12.8% improvement over the 5070.
This is why it is important to benchmark your intended workloads, as they will perform differently for various reasons – e.g. the required computations and how they were compiled/optimised. But I’d have to say that this was less of an improvement than I would have assumed.
Sensors
Using HWMonitor, we can read the chip-based sensors which seem to report just fine. There are no board-based sensors that were identified, perhaps because of a lack of SMBus driver being installed by default.
Thermals and Power Consumption
Testing of thermals was done by running Prime95’s torture test on the maximum heating option available for one hour in a room with still ambient air of about 18-20 degrees C.
Exterior temperatures based on thermal images taken with a Topdon TS001 were reasonably low at 43.7 degrees C. Internal temperatures as seen through the grilles are a bit higher, about 56.7 degrees C. On the whole, the exterior surface would be similar to the 5070. However, the internal monitors seemed to tell a slightly different story, with the package temperature topping out at 76 degrees C under 119.2% maximum utilisation with a maximum package power of 7.98W. This makes it slightly warmer inside than the 5070, but not significantly so. The power adapter reached a hot-spot of about 44 degrees C, quite a bit warmer than the 5070’s power adapter, but this may be because of the lower power rating resulting in a higher percentage utilisation of its rating and smaller physical size. It is still not critically hot.
Power consumption was measured from the AC side using a Tektronix PA1000 Power Analyser and the supplied power adapter provided 230V 50Hz from a synthetic pure sine-wave source under a few different situations. In all cases, Ethernet was connected at gigabit speeds.
With the unit shut down, the unit drew 1.3W from the wall. Under Windows, idling at the desktop with a keyboard, mouse and 4K display attached, it consumed about 10W. Removing the peripherals dropped this to 6W. Under a working load with Prime95, the load increased to 25.1W and 21.2W respectively. Peak power was higher – readings of even 30W were seen transiently. This configuration was done with a Lexar NM610PRO NVMe SSD (not the shipped configuration).
Under Ubuntu 24.04 LTS Linux, idle power with peripherals attached was measured at 7.9W which dropped to 4.2W without peripherals. Under mprime, readings of 22.9W and 20.9W were obtained, all slightly less than the Windows readings likely because (in part) this configuration was the shipped configuration using the included eMMC. As I only discovered how to install Windows onto the eMMC late in this review, I don’t have a true apples-to-apples comparison.
I also tried to do some measurements when powered via USB-C PD using a Fnirsi FNB58 under Linux. Idle power was measured at 6.4W with peripherals and 4.1W without. Under load, power was measured at 19.7W with peripherals and 17.8W without. When shut down, power was measured at 1.2W.
The power readings suggest that this unit will use more power than a 5070 but only by a few watts. It is still a relatively low power consumption compared to a full-fledged desktop.
Storage
The t640 can support M.2 SATA, M.2 NVMe and eMMC storage. Mine shipped with a 64GB eMMC pre-fitted, so I decided to test its performance under Linux.
It seems that the average read speed was 176.8MB/s. Write testing could not be performed since Linux was installed to the eMMC at the time, but I don’t expect anything amazing as most SSDs will blow the eMMC out of the water performance-wise.
[ 1.296402] mmc0: emmc 1.8v flag is set, force 1.8v signaling
voltage
[ 1.297906] mmc0: SDHCI controller on PCI [0000:01:00.0] using
ADMA
[ 2.397974] mmc0: new HS200 MMC card at address 0001
[ 2.410062] mmcblk0: mmc0:0001 hC8aP> 58.2 GiB
[ 2.413600] mmcblk0: p1 p2
[ 2.414027] mmcblk0boot0: mmc0:0001 hC8aP> 4.00 MiB
[ 2.414890] mmcblk0boot1: mmc0:0001 hC8aP> 4.00 MiB
[ 2.416108] mmcblk0rpmb: mmc0:0001 hC8aP> 16.0 MiB, chardev
(241:0)
[ 2.542668] EXT4-fs (mmcblk0p2): mounted filesystem
7b9dbfaa-892c-4aec-9f43-24999bc325e2 ro with ordered
data mode. Quota mode: none.
[ 3.193241] block mmcblk0: the capability attribute has been
deprecated.
[ 3.419144] EXT4-fs (mmcblk0p2): re-mounted
7b9dbfaa-892c-4aec-9f43-24999bc325e2 r/w. Quota mode:
none.
Based on the dmesg output, it seems that the eMMC is an HS200 device or on an HS200 bus, so 200MB/s is the maximum one can expect anyway.
CID: 90014a68433861503e02105edc323800 CSD: d02700328f5903ffffffffef8e400000
For reference, the above is the reported CID and CSD register values, suggesting the device is a Hynix H9HP52ACP… device. I won’t know for sure unless I peel off the label, but I don’t feel like doing that …
I did stuff my ailing Lexar NM610PRO in there for some NVMe testing.
It boots and it runs at the full PCIe 3.0 x 4 speed. That’s about as good as one can expect in a refurb when it comes to storage and much better than the 5070’s SATA.
Of course, the throughput was probably slightly limited by the drive’s poor YMTC flash and controller but it’s still a very fast result for an otherwise moderately-slow box.
Graphics
I did a quick check of the GPU capabilities using GPU-Z. It detects the AMD Radeon Vega 3 graphics processor, with DirectX 12_1, OpenCL, DirectCompute, DirectML, Vulkan and OpenGL 4.6 capabilities. It claims a 2GB memory size, but this is “stolen” from system RAM. As a result, Windows reports just 5.92GB usable on the t640, while 7.82GB is usable on the 5070. In spite of this, I still felt the t640 was noticeably snappier running my 4k monitor with fewer stutters – this might be a combination of the better graphics performance and the NVMe SSD I used to test Windows. It’d still be a bit slow to be a primary everyday machine.
Installing K-Lite Mega Codec Pack, acceleration seems to be detected and checked for H.264, HEVC, HEVC10 and VP9. Given the age of the unit, lack of AV1 is understandable. VC-1 is unchecked but seemingly also available given the DXVA data copied below.
I copied the data from GPU-Z’s DXVA Decode page. It seems it will decode most formats, although unlike the Intel iGPU of the 5070, there is no claimed support for 8k. This isn’t likely a big deal, as the outputs are generally limited to 4k anyway and I don’t see a market for people to assemble an 8k display out of four 4k displays attached to an old thin client. As usual, there seem to be some unknown formats in the list as well.
DXVA 2.0 Video Decode Supported Yes H.264 multiview variable-length 9901ccd3-ca12-4b7e-867a-e2223d9255c3 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No H.264 stereo high profile f9aaccbb-c2b6-4cfc-8779-5707b1760552 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No H.264 stereo high profile, mbs d79be8da-0cf1-4c81-b82a-69a4e236f43d Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No H.264 variable-length, no film grain 1b81be68-a0c7-11d3-b984-00c04f2e73c5 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No H.264 variable-length, no film grain, Flash 4245f676-2bbc-4166-a0bb-54e7b849c380 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No HEVC Main 10 profile 107af0e0-ef1a-4d19-aba8-67a163073d13 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No HEVC Main profile 5b11d51b-2f4c-4452-bcc3-09f2a1160cc0 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No MPEG-2 IDCT bf22ad00-03ea-4690-8077-473346209b7e Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No MPEG-2 variable-length ee27417f-5e28-4e65-beea-1d26b508adc9 Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No MPEG-4 Part 2 variable-length, Simple & Adv. Profile (Avivo) 7c74adc6-e2ba-4ade-86de-30beabb40cc1 Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No MPEG-4 Part 2 variable-length, Simple & Adv. Profile, no GMC ed418a9f-010d-4eda-9ae3-9a65358d8d2e Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No VC-1 variable-length 1b81bea3-a0c7-11d3-b984-00c04f2e73c5 Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No VP9 profile 0 463707f8-a1d0-4585-876d-83aa6d60b89e Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No VP9 profile 2 10-bit a4c749ef-6ecf-48aa-8448-50a7a1165ff7 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown 00000000-0000-0000-0000-000000000000 Supported Yes Unknown 2db154b6-dbb2-4079-a3ff-60d7a898a6ab Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown 514a356c-7027-4aff-8a60-afd2c1f672f1 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown 5ef7d40d-5b96-49e7-b419-23342094a4cf Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No Unknown 65d1fa41-58af-453a-9cab-5d981156da9f Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown 6719b6fb-5cad-4acb-b00a-f3bfdec38727 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown 725ad240-786c-471e-ad3c-38f739936517 Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No Unknown 84ad67f6-4c21-419a-9f0b-24f0578906c1 Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No Unknown 95664ff5-9e03-4c74-bb4f-9178d6035e58 Supported Yes 480p No 720p No 1080p No 4K No 8K No Unknown c152ca8f-738c-461b-ad89-fc292cf8f162 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown c58b9a06-7e89-11e1-bb00-70b34824019b Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No Unknown c74a3fd0-d713-4581-a02e-8edfb112ace3 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No Unknown ca15d19a-2b48-43d6-979e-7a6e9c802ff8 Supported Yes 480p Yes 720p Yes 1080p Yes 4K No 8K No Unknown d1c20509-ae7b-4e72-ae3b-49f88d58992f Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K Yes Unknown ea72396a-67ec-4781-bede-56f498f04ef2 Supported Yes 480p Yes 720p Yes 1080p Yes 4K Yes 8K No
Upgrades
As usual, I’m always not quite satisfied with what I have, so I decide to tinker with it and see how far I can push things.
First thing’s first – that eMMC is eating up a very previous M-key slot. How about I move it into the E-key Wi-Fi card slot? To do this, I bought a cheap adapter from AliExpress. It is a bit long because of the stacked connector, to the point it overlaps the USB-C option board. I had to cut the adapter a bit to allow the cable connector to clear the adapter and find my own screw to mount the adapter into place. It’s not quite flat, but should make sufficient contact to operate.
Because the screw-head is a little tall and there are some capacitors on the back of the eMMC card, I used a bit of yellow plastic to insulate the two. Gently screwing the sandwich together, I was able to get the unit secure enough to give it a run.
The eMMC still had Ubuntu installed on it, so I was quite happy to see that it booted right away despite being in the Wi-Fi card slot. I’d call this a win …
… as this means I can now have an NVMe drive at PCIe 3.0 x 4 in the main storage slot and the eMMC running at the same time. Performance of the eMMC is unaffected too, as tested in Linux, purely because the 200MB/s won’t exceed the (presumably PCIe 3.0) x 1 capability of the slot. Alternatively, the daring might even fit an NVMe 2230 drive in there and find lower performance, but still, nice to have more storage inside the box. This also explains the Windows 11 install screenshot earlier that showed two drives – the NVMe (with Windows) was Drive 0 and the eMMC (with Linux) was Drive 1. As there’s some space, the main storage slot can accommodate a heatsink above the NVMe drive as well.
To top off the build, I also decided to change the CMOS battery pre-emptively, to avoid any unscheduled downtime. I’m used to seeing KTS, Newsun CR2032 cells, but DBV (Double Best Corporation) is a new one.
Conclusion
The HP t640 is a nice alternative to the 5070 if you can get it for a good price. Aesthetically, it’s a bit nicer with its rounded edges and it’s also a little more steady with a wider base at the cost of taking up more desk footprint. It has a more powerful AMD Radeon Embedded R1505G CPU with better graphics that feels a bit snappier in interactive use than the 5070. It does use a few watts more power, but is still relatively power efficient with a compact 45W power adapter. Being passively cooled, it manages to be quiet and have similar temperatures to the 5070 of about 50 degrees Celsius externally and 76 degrees Celsius on the package.
Perhaps the biggest benefit is that this unit is capable of running up to 2280-size NVMe and SATA M.2 SSDs rather than being restricted to just SATA M.2. The slot runs at a full PCIe 3.0 x 4. The included eMMC does require a driver load to get Windows 11 to install, but Ubuntu recognised it just fine. There were a few isolated instances where boot seemed to hang due to waiting for the eMMC. Performing BIOS updates are a bit more painful than the Dell, requiring a Windows 10 computer to build a recovery flash drive which may not work depending on the filesystem (ideally, use a <=32GB USB flash drive).
Another benefit is the availability of 10Gbit/s USB 3.x ports. If you get lucky and get one with a USB-C DP output card option pre-installed, then you’ll also have the fortune of being able to use USB-C PD power as an option to using the proprietary power adapter which is a nice addition.
