Examples of Poor Design, Engineering, and Implementation of Computer Systems and Their Components
2018.08.27 ｜ Yuki Rea
I have years of experience in computer science and engineering as a hobby and as a business, I have spent most of my life thus-far working with computers in some form. I have encountered, worked on, and owned many computer systems including servers, laptops, desktops, and portables. From this experience I have learned what it takes to make a great computer system and what the common pitfalls are. This is a collection of the absolute worst systems I have ever had the displeasure to deal with. This article will continue to grow as I have time to add more systems and come across new ones.
I must state beforehand that I do not mean to pick on HP specifically, well maybe just a little. Many of the organizations and businesses that I associate with all use HP hardware so I have access to far more HP systems than other manufactures.
HP ProBook 4525s Laptops
I acquired a handful of these to help diagnose their poor network performance for a client. My experience with these machines convinced me that they are hands-down the worst laptops I have ever used. These laptops have a variety of hardware problems that make them infuriating to use in most circumstances.
Keyboard
My first reaction to using one of these machines was that the keyboard is the worst keyboard that I have ever used. The keyboard has shallow island style keys which are made of very thin and flexible plastic. This is half expected from budget notebooks, the real problem comes from keys not registering unless pressing them in the exact center with excessive force. This dramatically decreases the words per minute one can achieve on this keyboard and causes wrist and finger pain after prolonged use, far more than I have ever experienced using any other system. Even the space-bar has to be pressed in the exact center to register the key-press, just awful.
Trackpad
Like the keyboard, the touchpad is one of the worst in the industry. It is a touchpad with no individual mouse click buttons with just a single switch mounted underneath, your finger position on the touchpad determines if a click was a left or right click. These designs are annoying to begin with, but add in the random mouse movements that can traverse the entire screen in an instant makes doing anything with this touchpad nearly impossible.
Component Access
Another minor gripe I had with this laptop was access to the internal hard drive, it can only be accessed by disassembling most of the machine. This makes swapping the drive impractical for most users. I often swap different drives in and out of my computers with various Operating Systems on them. Needing to completely disassemble the machine every time became infuriating so I cut a hole in the wrist rest to allow easy access to the drive, problem solved.
Cooling
The 4525s was one of my first experiences with HP's 'put no intake vents in the case' phase of laptops. The bottom of the laptop's case is all plastic with one tiny slit in the case that restricts the amount of air that can enter. This vent is so restrictive that the fan has to work very hard to pull any air into the machine. Airflow can even be felt entering through the gaps around the optical drive because the vent is not large enough to allow sufficient airflow. Cutting a hole in the case directly under the intake fan reduces CPU and GPU load temperatures from over 90c to ~80c. The noise level of the fan was significantly quieter after this modification. It always amazes me how many problems can be solved with a simple rotary cutting tool.
Wireless Modules and PCIe Device BIOS Whitelist
Now to finally address the reason I acquired these machines in the first place, their horrible network performance. During my testing, all laptops only managed to reach a maximum wireless transfer rate of 7Mib/s. That is Mebibits not Mebibytes, this is slower than most rural DSL connections. Okay no problem then, swap the wireless module for a $20 Intel one and call it a day, right? This is not feasible due to HP's device white-list that is hard-coded into the BIOS and prevents the system from booting if a device that HP has not approved is installed. Many systems have white-lists, they are usually used as a tactic to force you to buy overpriced parts with custom vendor specific identifiers directly from the system manufacturer. Most of the time these white-lists are not a big problem if there are enough officially supported devices to chose from. HP decided to only add 3 wireless devices to the 4525s white-list, all of which are just as slow as the one the laptop shipped with. There are only two ways to get around this restriction, the first way would be to modify the firmware on the wireless module to have the same identifier of a device already in the white-list. The other method is to completely disassemble each laptop, dump the BIOS ROM with a hardware programmer, modify the ROM to remove the white-list or add your device to it, flash the modified BIOS ROM with the hardware programmer, and reassemble the laptop again.
Conclusion and Re-usability
By now we have determined that this machine is basically unusable as a laptop, maybe the motherboard can be removed and used for something else like an HTPC or arcade machine. Unfortunately even this is not practical because the initial display output can not be changed from the internal LCD to HDMI. The only way to use the HDMI output is to enable it inside the operating system after it has finished booting and has loaded the graphics driver. It is unfortunate that such an attractive and sleek looking machine has so many major flaws.
HP Pavilion 17-F262NR and Similar Laptops
Like the ProBook 4525s, this series of laptops suffers from chronic cooling issues. This time to an even worse extent, in the stock configuration the laptop overheats and powers off due to overheating caused by a combination of issues. This laptop also features a terrible keyboard and trackpad, while not pleasant to use, it as at least functional unlike the 4525s.
Cooling - Ventless Intake Design
This series of laptops also features a design with no vents on the bottom of the casing. Instead, the majority intake air enters the system though the keyboard. There are holes in keyboard backplate where the system fan is located to allow air to intake between the keys on the left half of the keyboard. This does create a nice breeze over your hands, however it does not allow enough airflow to keep the processor cool in anything more than basic usage.
Cooling - Windows 8 Only CPU Fan Driver
In addition to the poor physical cooling design, the CPU fan control scheme is based entirely on software. You may already imagine how this is a very bad idea, malfunctioning software and the fan control may no longer work. This software is called "HP CoolSense" and is a Windows 8 only fan driver which is used to detect the system temperature and control the fan based on that. The problem is that the fan will remain idle until the driver is loaded and functioning. If another operating system is installed, Windows is preforming an update, or the driver stops working, the CPU fan speed will not increase and the system will overheat. I had constant problems with the HP CoolSense driver, it seemed to be broken more often than not resulting in the system overheating and powering off with even basic tasks like web browsing or watching a video. Windows update would also cause the laptop to reboot when installing updates before the driver is loaded. The only time the fan control works outside of Windows is in the BIOS setup utility.
Keyboard and Trackpad
This laptop uses a low travel keyboard with island style keys, the keyboard typing experience itself is not pleasant but mostly functional. You will not be setting any speed records with this keyboard but it at least registers keypresses, most of the time.The keyboard feels fragile and flimsy as does the rest of the laptop. Going back to the keyboard being used as an air intake for the cooling system as I mentioned earlier, this causes dust to accumulate underneath and between the keys. Once enough dust has built up it prevents the keys from fully depressing and no input is registered. Cleaning the dust is very difficult because there is no easy way yo remove the keycaps to get underneath them. You have to resort to compressed air and scraping the dust out from under the keyboard with whatever you can manage to fit under the keys. The trackpad is a buttonless design making holding a mouse button while moving the cursor difficult (drag and drop). Pointing with this trackpad is also inaccurate and the palm rejection is poor resulting in selections being made when your wrist brushes up against the trackpad while typing.
HP Compaq 6910p Laptops with ATI Mobility Radeon X2300 GPU
The HP Compaq 6910p is an example of how a great system can also have flaws which cause major problems later in the products lifespan. I acquired a not-insignificant number of these systems to part out and refurbish. Half of them all had the same issue, a dead or malfunctioning GPU.
Cooling
Most of the laptops had dead or artifacting GPUs. I believe all of these GPU's died as a result of one single mistake that HP made in the cooling system. HP opted for thermal pads as opposed to thermal past as a thermal interface between the GPU and heat-sink. Thermal pads have a worse thermal conductivity than a thermal paste, in this case it causes the GPU to run over 100c for long periods of time. Replacing this thermal pad with proper thermal paste nets a 20 degree drop in temperature and allows the GPU to stay within safe operating temperatures.
PCIe Device BIOS Whitelist
The 6910p, like most of HP's product range, also has the infamous BIOS white-list. Fortunately the BIOS ROM is flashable via the OS. It would be nice to see the white-list removed all togather in the first place, but having an easily flashable BIOS ROM makes modifying the original BIOS to remove the white-list a much more approachable endeavor.
HP Proliant ML350 G5 and G6 Servers
I was given two HP Proliant ML350 servers by a local school when they last upgraded all of their IT hardware, one of them being a G6 and one G5. These systems both suffer from the same problem, cooling.
Cooling Implementation - Drives
Each server has 4 exhaust fans that pull air through the entire system and do a great job of cooling the processor/s, memory, and various other components on the mainboard. The processors of each system never really exceed 50c with the fans at a reasonable RPM. However, HP located the hottest components in the system as far away from the cooling fans as possible and put almost no ventilation near them. The components I am talking about are the 2.5in SAS drives which sit in a hot-swap bay at the bottom-front of the case. The only way for air to flow through the drive cage is through a few tiny holes cut into the backplane PCB of the hot-swap bay. After just a few minutes of idle use with the drive bays populated, the system fans will reach their maximum speed creating a deafening noise while not actually cooling the components that are heating up. Instead they pull almost all of their cool air through the 3.5in drive bays which have nearly unrestricted airflow. If the SAS drive array is under any significant load, the drives will overheat and cause the entire system to power down.
Cooling Implementation - Power Draw
HP's poor prioritization of cooling resources results in a significant increase in power draw from the fans in order to attempt to move enough air to cool the drives. The fans alone at full speed actually consume more power than the components they are typing to cool idle. I measured the power draw of each fan individually at full speed outside of the system. Each fan consumes up to an insane 25w of electricity, with 4 fans this totals 100w of wasted power just to compensate for a poor design choice.
Cooling Implementation - Remedy
HP could have solved all of the cooling issues by making bigger holes in the backplane PCB or just adding another fan near the drive cage. I use the G6 server as my home server and have solved this by installing an 80mm fan behind the drive cage. This single fan dramatically decreases the drive temperatures and causes the system fans to never increase over their minimum RPM unless the room ambient temperature reaches ~40c. If adding aftermarket parts is not something you are comfortable with, ensuring that drives in the hot-swap bay are spaced out can also help with cooling.
MSI GA-970A-G46 Motherboard
The worst modern motherboard I have ever owned, I have had two of these motherboards and both experience the same problems. An inadequate CPU VRM plagues this motherboard in addition to an infuriatingly broken BIOS setup utility.
Inadequate CPU VRM
The CPU VRM is unable to keep an AMD FX 8350 processor stable even at stock speeds despite being listed as "Supported" on MSI's official product page for this motherboard. Even the lower TDP and core count FX 6300 causes these boards to occasionally lock up and reboot unless under-clocked. There have been reports from other owners of this motherboard that the VRM completely fails when using 6 and 8 core CPUs.
Physical Layout
My other issue with the hardware aspect of this motherboard is that 2 of the SATA ports are not right-angle connectors and stick out vertically from the motherboard. These are positioned inline with the 2nd 16x PCIe slot so that they will interfere with most cards installed in that slot. This means you have to chose between installing an expansion card in this slot or more than 4 SATA devices. Many motherboards have similar layout problems but usually these connectors are near the bottom edge of the board where they are less of an issue.
UEFI BIOS Setup Implementation
The last of the problems with this motherboard all result from a poor UEFI/BIOS setup utility implementation. Fan control seems to be very broken. When fan control is set based on temperature, the CPU fan makes hard jumps from a low idle RPM to it's maximum speed seemingly at random even when observed temperatures remain low. Sometimes it will remain at it's maximum RPM until a full reboot. The UEFI BIOS also often fails to save or ignores settings indefinitely or until rebooting and re-applying the setting multiple times in a row. It took me about 30 minutes just to turn off the blue LEDs next to the CPU power input connectors.