Upgrading a PC's memory resulted in screeching sounds whenever it tried to play audio. Has this ever happened to you?
Last week, I helped my father-in-law's friend by upgrading her PC's memory from 2 Gbytes to 4 Gbytes. Simple, right? I've done memory upgrades many times on both desktop and laptop PCs without incident, but not this time. Why did this bizarre side effect occur?
The PC in question is an HP/Compaq dc5750 desktop unit. It originally ran Windows XP but was upgraded to Windows 7 by a local computer dealer. It has 2 Gbytes of DDR2 RAM. It runs decently, but would surely run faster with 4 Gbytes. After three visits in four days, I ended up restoring the PC's original memory. Here's what happened.
On the first visit, (Thursday) I documented the PC's existing memory. Figure 1 shows the PC.
Figure 1. The PC in need of an upgrade: An HP dc5750 Microtower
After opening the PC, I found four 512 Gbyte DDR2 memory modules, removed one, and photographed it before reinserting it and closing the case.
Figure 2. The PC had four 512 Mbyte DDR2 memory modules, totaling memory 2 Gbytes. That's just enough to run Windows 7.
The local Best Buy doesn't carry DDR2 memory, but fortunately, I found what I needed at Micro Center. Returning on Saturday with two 2 Gbyte DDR modules, I expected things to go smoothly. Silly me.
After replacing the four 512 GB modules with the two 2 Gbyte modules, I started the PC. It booted normally after I confirmed that the BIOS correctly identified the new memory. But, there was an unexplained wide effect: Whenever Windows made a sound, it literally screeched. Listen to the sound, if you dare. It should sound like the familiar windows chime.
While the PC did work, the screeching was too annoying. Yes, I could have set all windows sounds to off, but that's not the point. So, I removed the new memory and reinstalled the old modules.
Thinking that perhaps one of the modules was defective, I returned the first set to Micro Center and tried modules from a different manufacturer, which cost $5 more per module. Figure 3 shows one of modules.
Figure 3. Here's one of the two second-try memory modules.
Figure 4 shows the package.
Figure 4. According to the packaging, this memory module should be compatible with the PC.
The second pair of memory modules (installed on Sunday) produced the same screeching sounds as with the first. So once again, I set the back to its original 2 Gbytes of memory and will return the second set to Micro Center.
I've never seen nor heard of such strange symptoms. Have you? Did I miss something? Please let me know what else to try.
Martin Rowe covers test and measurement for EDN and EE Times.