There is far more than just the BIOS involved -- the mainboard is likely engineered to support 8 G of RAM total, regardless of what the chipset and CPU support. This is not a high-end, high-performance system and wasn't designed to be one. It's a mid-range multimedia system, and price constraints being what they are (people will literally choose one model over another with as little as a $5 price difference), it's been designed to meet a price point.
Very few notebooks have extensively tune-able BIOS settings - for that you need to go for an enthusiast system. They're out there - but not at the price of an Inspiron.
I have read that there is a BIOS update that allows the system to access the full ability of the CPU, DDR3 1600 and a total of 16GB via two sticks of 8GB, each. I don't have the need to test this, as playing with BIOS isn't fun for me. I'll go for the DDR3 1600. It's actually cheaper than 1333, nowadays. I can get by with 4GB, but 8GB will keep bottlenecks at bay as software inevitably gets more complicated as time passes.
Recognition problem maximum amount of RAM after updating bios
I have a strange problem, after updating the bios of my Dell Inspiron 5520 to version A14, change the maximum size of RAM it was before in 16 gb and now change to 8 gb.
currently I have 6GB of ram.
Someone could recommend me which ram memory model must choose between these 2 models available in my country.
1) Crucial 16 gb kit (8gbx2) DDR3-1600 mt/s (Pc3-12800) 204-pin SODIMM
2) Kingston HyperX impact black 16gb kit (2x8gb) 1600 mhz DDR3L CL9 1.35v (Hx316LS9IBK2/16)
What would be the best option.
Unless you absolutely need more than 8GB, I'd go for 2x4GB 1600 Kingston. You could end up wasting your money, and there is one user on this forum whom exceeded the 8GB limit ended up actually slowing his machine. Granted, this user installed mismatched sticks in a dual channel set: one 4GB + one 8GB, which is just asking for trouble. Device Manager listed the full 12GB, but the description page only recognized 4GB. This was done after updating to the most current BIOS.
If you need more than 8GB, try going back to the previous BIOS and hope that the 16GB possibility returns. If it does, I still recommend the Kingston. They advertise that their RAM will automatically adjust itself depending on the chipset. For this reason, I'd go for the 1866. It will underclock to 1600 or even 1333 and tighten up the timings, lowering CAS Latency as much as it can while remaining stable. But check out rolling the BIOS back to be sure it grants your wish of 16GB. More RAM, Mo' better.
Today, I upgrade my Inspiron 15R 5520 to 16GB. The laptop is functioning normally, I used kali Linux (That doesn't really matters), I made a Bios update (A14) cause I was receiving a constantly beep when I tried to put both 8GB DIMM (2 X 8GB ADATA 16GB 1600mhz) on the laptop, one of the memory is DDR3L an the other just DDR3 as it puts on the label. I finally could made both memories, putting the DDR3L in the down slot (slot 2 or secondary slot), turn on the laptop, enter to the BIOS, I verify that the memory was readed (Obviously it was readed cause the laptop was on, just double checking), turn off the laptop, put the another DDR3 memory on the primary slot, and turn on again, laptop didn't make constantly beep sounds, I entered to the BIOS to verify the memory amount readed by system, 16GB, and after that I boot to Kali Linux. I verify on the OS and it was 16GB on system. I made a RAM test with memtest command to see if memory ram it doesn't has any bug. Everything is perfect. Is impossible that one equipment with a 3rd generation processor like Intel I7 3612qm (6MB L3 Cache) just support 8GB of RAM, That processor is a kind of Leviathan and 8GB is nothing for him. The thing is that for Dell there is not business if you keep up with your laptop 3 - 7 years without changing it. Same thing for mobile devices. They just wanna take out the money out of ours pockets. For Tech enthusiast like me, to change a laptop or even OS every year can be a headache.
Today I got 2x8Gb CRUCIAL DDR3L 1600 CL11 memory sticks. My Inspiron 15R 5520 is running the A14 bios update. No issues found, so far. Running smooth under Gnome Ubuntu. For testing I opened a huge dataset that aet almost all ram memory with no issues (about 600million cells). Later I ran a Hortonworks Docker that needed about 11Gb of memory also with no issues, no hangs... Pretty happy.