Chosen Solution
I have a Latitude E6440 (i5-4310M/AMD 8690M 2GB/HD 4600) I am working on qualifying as a replacement for my i5-4300M/HD 4600 model, which has issues with the motherboard USB ports and it is showing the early warning signs of failure. Due to the early warning, I am preparing to get a unit ready so I can replace it and then use the old one for parts - these boards are about as much as the systems, so replacing the board doesn’t make sense. However, when I was qualifying the machine I noticed a weird firmware level issue where if I Ctrl+Alt+Delete out to reboot, it “sleeps” instead of restarting. When this happens, the machine boots but shows DIMM slot empty despite RAM being present. This has happened with new Yongxinseng and Crucial Mac RAM, so it has happened with 2 sets so far. I also tried some known good Ripjaws with the same effect. I have also put a E7440 IPS LCD in, so I went back to a known match from the E6440 series (768p). Even when I go back to the “correct” LCD (even though this shipped with FHD, but I had to reuse a screen because of Covid), it still occurs. I have also disconnected the trackpad, WiFi switch and volume buttons with no change. I have also tried without the wireless card - again, no change. I have also pulled the CMOS battery and installed the A24 BIOS as well, and it’s still happening. At this point, I am stumped and am seriously considering a early disqualification as the final replacement system.
@jayeff Another update. I took this system replacement in a completely different direction then I was thinking I would. I primarily made this decision because I have 3 batteries for these (2 OEM/1 aftermarket) and the performance of the i7-4600U is similar to the i5-4300M, and I’m not going to need batteries for a little bit since my 6440 battery is a far cry from what it used to be even months ago and I need to replace it anyway - ePSA fail tired*. This originally ran Win8.1 Pro with a 128GB M.2 SSD in an adapter** since I bought it no RAM or HD. I wanted it to be as identical as possible, so I installed 10 and ditched Win8.1 Pro. Sadly, Win8 is showing it’s age with degraded SW/HW support. *I was able to coax it back to “fair” health, but once it fails ePSA it’s time to replace it. **Dell also did this with the SM841N mSATA SSD as well as a 5mm mSATA interposer on some, so I did something similar with a enclosure from eBay. Mine shipped with the WWAN slot populated with the 128GB SM841 SSD before it was removed. I did cheat here and I do need to get the factory bracket installed since I put it in bare and use the bottom cover as the support. It’s not as necessary on the 7440 as the clip on the 6440 is, but it makes it look like shade tree tech work without. What I did was I had a 7440 I got for parts thinking it was LVDS and shelved it because it had the 768p TN (read: garbage) LCD BUT I was very surprised to see EDP printed on the motherboard because 768p usually indicates LVDS - display cable also said EDP so it was a match :-). After I found it could accept the FHD LCD (IPS), I put it in the laptop and then moved the 240GB SSD from the 6440. I got the retain the NO CAM setup, so double score. I’m not in Zoom school, so I’m using that choice. I now need a external DVD drive, but they’re cheap. Been running this since 2/22. I’ll mess with the LVDS 6440 later to see if it’s truly bad, but this fixes my biggest gripe and I know it’s all good and I will not have to worry, as it’s vetted.
