Sunday, April 27, 2025

i7-7700K (2017) iMac problems

After selling my 2017 i5 iMac to a woman from Scottsburg and setting up my 2020 iMac, I needed to prepare my recently purchased 2017 iMac (with an i7-7700K) for resale.

The first step was to remove the Windows partition and erase everything on the computer — and that's where the problems began.

I used Boot Camp to remove the Windows partition I had previously created, which should have reclaimed the 1.6 TB I had allocated to Windows. While the program successfully deleted the partition, it reported an error when attempting to reclaim the storage space. I then tried using Disk Utility (the Mac partition tool), which also failed and told me to try running it from Recovery Mode, which didn't work.  A few years ago, I tried the same thing on my old, dying 2009 iMac, and that attempt had failed too.

Newer iMacs have a built-in feature to securely erase everything automatically, but while the option exists in macOS, it doesn't actually function on older models. So, the recommended method is to boot into Recovery Mode, reformat the drive, and reinstall the OS — a process I had successfully completed on the iMac I just sold.

Unfortunately, the 2017 iMac with the i7 processor reformatted the drive but threw an error during the OS installation. It simply refuses to install. At this point, I have a $400 paperweight with no operating system.

I'm starting to wonder if the 2 TB hard drive might be defective.  It is, after all, an eight-year-old computer.

Next, I'll try creating a bootable USB flash drive with the macOS installer using my 2020 iMac. According to everything I've read online, that's the recommended next step if the OS won't install through Recovery Mode.  It is probably what the repair shop would try.

Friday, April 25, 2025

My Lengthy iMac Story

My Lengthy iMac Story:

Because of rapid advancements, computers quickly become outdated. From 1995 to 2010, I bought a new computer roughly every five years. I remember telling my coworkers in 2001 that my new machine could boot up in just 2.5 minutes—they were impressed. But how could a computer I considered "fast" in 2001 feel like junk by 2005? And the cycle repeated itself in 2010.

However, during the 2010s, the pace of chip improvements slowed. Companies were touting only 5–10% performance gains each year. A big reason was that it became increasingly difficult to shrink chip circuits. Intel got stuck at 14 nanometers. It wasn't until 2020, when Apple introduced its M-series chips—starting at 6nm and shrinking to 4nm—that we saw a meaningful leap forward. Much of the credit goes to TSMC (Taiwan Semiconductor Manufacturing Company), which produces chips for Apple and many other companies.

My first Intel-compatible computer, which I bought in 1995, cost $1,200. It was a barebones 486 running at 33 MHz, lacking features that are standard today. Over time, I Frankensteined it—adding a sound card, optical drive, better processors—one component at a time. By the time I had spent $3,000 on it, it was so obsolete that it made more sense to just buy a new machine. Newer computers came with all the features pre-installed and cost much less.

In 2010, I bought an iMac because I wanted to do iPhone app development. It cost $2,000, already discounted from the original $2,400 price. If I had known it would take me so long to get into development, I probably wouldn't have bothered. I could have bought an equivalent PC for about a third less.

That 2010 iMac had a quad-core 2.8 GHz i7 processor with hyperthreading. At the time, it felt incredibly powerful—a huge upgrade from anything I'd used before. I told myself the higher cost was justified since it would last ten years.

About three years in, the power supply failed. One issue with iMacs—and all-in-one computers in general—is that they're harder to repair and more prone to overheating due to their compact design. By 2018, the power supply was failing again. A repair shop told me several components were on the verge of dying and that fixing it would be cost-prohibitive. By 2019, the machine was completely dead.

So, in 2019, I went shopping for another iMac. I found a used 2017 i5 model—twice as fast as my old one—for $1,050, which was a fair price at the time. I wanted an i7 version with hyperthreading, but those were going for $1,950 used.

By 2023, even this second iMac felt slow. The Android development tools I needed were nearly unusable due to performance issues. I realized I needed a faster computer—just a Windows machine for Android work. I could still use the iMac for iPhone development. So I bought a mini-PC with a 4nm AMD chip—five times faster than the iMac and capable of booting Windows 11 in just 7 seconds. Amazing.

However, mini-PCs can suffer the same heat issues as all-in-ones. They all use laptop components and compact cases. After 14 months of heavy use, mine overheated and died. It took three months to get repaired in China. Interestingly, the machine I got back was a bit faster. It was the same case, but I suspect some internals were swapped. The company wouldn't tell me what they fixed.

Then, in March 2025, a series of storms in Indiana triggered the next chapter in this saga. After several power flickers, my iMac died the next day. I brought it to a repair shop and, learning my lesson, bought a couple of surge protectors—which I highly recommend.

With my mini-PC still in China, I was stuck using an old laptop. Surprisingly, it streamed video just fine.

Worried that the iMac repair would be expensive, I started browsing for replacements. On Facebook Marketplace, I found a 2017 i7 iMac in Louisville—the same model that used to cost $1,950—for just $400. It was 60% faster than my i5. I was ready to buy it. But two things changed my mind: First, my i5 repair ended up costing just $50—a power supply cable replacement. Second, I admitted to the seller that I was nervous about the long trip to the south side of Louisville. I told him I didn't need two iMacs. He suggested I could sell my old one and even dropped his price by $50. That sealed the deal. I drove to Louisville on a day of severe flooding, had to turn around, and eventually found another route.

After buying the i7, I listed my i5 for $300. A buyer was interested, but I accidentally cracked the glass front while handling it. The shop quoted $500 for the repair. Although the crack is minor, the buyer backed out. I lowered the price to $200 and plan to keep reducing it until someone bites.

Meanwhile, Facebook kept showing me more iMac listings. Two 2020 i7 models appeared—one in Louisville, one in Carmel—both for $500. The Carmel one had more RAM and storage, making it more appealing. These newer models were twice as fast as my recent purchase and came with SSDs, which makes a big difference. I started wanting one of these instead.

The catch: the Carmel seller mentioned a scratch and a tiny crack on the right side of the screen. Since I was already dealing with a cracked-glass problem, I initially passed. The next day, the price dropped to $430, and then today to $380. I messaged the seller, drove to Carmel in more stormy weather, and saw that the damage was very minimal—so I bought it. A great deal.

Now, I'm trying to sell two iMacs.

P.S. Yesterday, my barber told me her old laptop takes 25 minutes to boot. I suggested adding more memory, but she didn't even know what that meant. I offered to take a look at it for her.

Tuesday, April 22, 2025

The WORST iMac to buy

My Super Weird 2020 iMac "Review"

I see that two people are selling this computer for $500 on Facebook Marketplace.   I am tempted to get one.

This is an 8-core machine with 16 threads (hyperthreaded).  This is comparable to my 8-core mini computer, but less powerful.  This machine is 7% slower than the 8-core M4 chip.

My point is that there are cheaper options than Apple Silicon.   It can run Windows.  It is upgradable.

https://www.youtube.com/watch?v=EMFCVvy0rkE

Saturday, April 12, 2025

The best mini PC I've tested! Minisforum UM790 Pro

https://www.youtube.com/watch?v=ca_5e5Yrv8M

@john2001plus
49 seconds ago
After 14 months of heavy use, my Minisforum UM790 Pro overheated and died. I saw sparks come from the side.

After arguing with the manufacturer in China, they told me I had to send it to the seller, also in China, for warranty service. Fortunately, the seller was willing to help me. Unfortunately, I used USPS to send the computer to China, and it took 41 days to get there. Three weeks later, the seller sent the fixed unit back to me, using DHL, which only took four days!

Three months after the computer died, I was up and running again!

Sorry America - WAN Show

I don't listen to three-hour live streams, but this one talks for 7 minutes about the disruption of the computer industry.

https://www.youtube.com/live/TWb2P-GGBcU?t=137s

In this 8-minute segment, he defends the United States.


Monday, April 7, 2025

iMac for Sale

For Sale: 27-inch iMac with 5K Display – Excellent Condition I recently upgraded to a newer model, so I’m selling my beloved iMac. It’s in excellent condition, both visually and functionally. Key Features: 5K Display: With over a billion colors and a bright 500 nits, this display is one of the best you'll find on any computer. The display and the computer itself are both sleek and free from any damage. Powerful Processor: Equipped with a 3.4 GHz Intel i5-7500 quad-core processor, this iMac delivers plenty of power for everyday tasks. It's three times more powerful than my laptop, which I use for streaming videos. 16 GB RAM: With 16 GB of 2400 MHz DDR4 RAM, this iMac offers more than enough memory for typical usage. For an additional $20, I can upgrade it to 24 GB RAM. BootCamp: This feature allows you to install and run Windows 10. Windows 10 activation keys are available online for as low as $4. AMD Radeon Pro 570 Graphics: Perfect for light gaming and 3D tasks, with a performance of 3.94 teraflops—comparable to the Sony Playstation 4 Pro. Condition: The iMac is in great shape, with no scratches or damage to the case or display. Note: I will reset the device to factory settings before handing it over to ensure it's fresh and ready for you.

Friday, April 4, 2025

My Computer Being Shipped Back From China

My mini-computer, which took 41 days to ship to China using USPS, was shipped back to me on Monday using DHL Express.  It has already reached Indianapolis.  

https://t.17track.net/zh-cn?spm=a2g0s.imconversation.0.0.54c13e5f4Bq0lP#nums=9502219484

Tuesday, April 1, 2025

Magnetic Core Memory

512 byes of RAM costing $2,000:

https://www.youtube.com/shorts/mrBz9-9qgGw

One of the biggest limiting factors of early computers was the cost of RAM.  In the late 1970s, I remember seeing an advertisement for 64K of RAM costing $1,000.  Today, you can get 64 gigs of DDR4 for under $100.

This is why the Atari 2600 video game system released in 1977 only had 128 bytes of RAM.  

The first TRS-80 came with 4K.  The VIC-20 had 5K.

The Sinclair ZX-81 came with 1K.  Its American counterpart came with 2K.  Both were expandable to 16K.

The Nintendo Entertainment System, first released in Japan in 1983, had 4.25K RAM.

By late 1983, RAM had gotten cheaper, so we saw the Commodore 64 released with 64K, and the Timex Sinclair 2068 with 48K RAM.

The REAL TechDweeb

This is most likley an April fools joke, but maybe the real joke is that it is true.

Computer Failures

My 2017 iMac just suddenly quit on me last night. I think that I got it mid-2019.

This is my second computer to fail recently. It can have similar issues as far as heat. I wasn't doing anything major on it. I was only streaming video.

One possibility is the power supply died. This happened to my 2009 iMac and I got it repaired for reasonable cost. Twice. Eventually the 2009 iMac had multiple failures and I had to get a different computer.

I tend to leave my main computer running all the time. I was in the habit of leaving my iMac on too, but I started using the sleep mode.

It is probably a mistake to leave the computers running all the time. Some people claim it is better to do that, because the spike in power can wear electronics, but I just had two computers fail.

This means my only working computer is my slow laptop I got used, hooked up to a 1440P monitor.

Good thing I have three computers.

I paid $1050 for the iMac, which was reasonable at the time. I've seen the same model for sale on Facebook Marketplace for about $400-$450. I have also seen discounted Mac Minis.

Took my iMac to the repair shop. I would have to factor repair cost with getting a replacement computer.