Man from Milky Way

Hello again! Thank you all for the additional help! I have been out of the country and busy for a few days but I've managed to try these things: - reset BIOS via the motherboard jumper, - clean the dimm slots with an air compressor, - update BIOS to the latest version, - remove and re-insert CPU, and - ensure that the RAM was properly and firmly inserted. None of these measures have solved my problem; if I insert a module B1 or B2, my PC won't boot. Is there anything else I can try? P.S. I'm fairly certain the modules were purchased in one package, not separately.

OK, thanks still!

You've understood 100% correctly! I will try your suggestions! Thank you!!

Thank you! So is the instructions from the manual just really misleading? (In attached picture) It's even color coded in pairs Also, sorry to bother, but do you have any suggestion as to why my memory performance sucked with two sticks and was very good with just one? https://www.userbenchmark.com/UserRun/17362559 (two sticks in A1 and A2, respectively) https://www.userbenchmark.com/UserRun/17341862 (one stick in A1) Thank you again!

First, specs: RAM Manufacturer: Corsair Model: CML8GX3M2A1600C9 Capacity: 8 GB (2x4 GB) Frequency: 1600 MHz Motherboard Manufacturer: Asus Model: P8Z77-V LX DIMM Qualified Vendor List: link (it contains my RAM model but it lists it as 4 GB instead of what I'm guessing would be better: 2x4 GB but this might be irrelevant) Manual: link CPU Manufacturer: Intel Model: i5 3450 Max Memory Size (dependent on memory type): 32 GB Memory Types: DDR3 1333/1600 Max # of Memory Channels: 2 Max Memory Bandwidth: 25.6 GB/s Problem: My PC won't boot when my two memory sticks are inserted into DIMM_A1 and DIMM_A3, or DIMM_A2 and DIMM_A4 for that matter. The PC itself lights up, the device I have connected to a USB A outlet in the front lights up, but none of the devices connected to the back of the box do. Background: I have been using 2x4 GB RAM. I noticed two days ago that I had them set up incorrectly with the sticks next to each other (in slots DIMM_A1 and DIMM_A2) which led to terrible memory performance when measured in UserBenchMark. I do believe they were recognized as 8 GB in total by the PC however (I can double check this if it is relevant). I chose to rearrange the sticks by turning off the PC, unplugging, and then inserting them in DIMM_A2 and DIMM_B2, as this is how I interpreted the instructions in the motherboard's manual. I plugged in the power supply and turned everything on but the PC wouldn't boot. It wouldn't boot with only one stick in DIMM_A2 either IIRC when I rearranged the RAM using the same method. I then inserted the sticks in slots DIMM_A1 and DIMM_A3. Again, didn't boot. I now decided to use a button on the motherboard called "memOK!" which is mentioned in the motherboard's manual. Its purpose is to initiate a series of tests with different BIOS memory configs until successful boot, a nifty function that got my hopes up for a moment, but yet again, no dice. Last test was to use only one stick in DIMM_A1, which did result in a boot. In addition, I got improved (RELATIVE) memory performance in UserBenchMark. Unfortunately, of course, now I have only 4 GB of RAM instead of 8 GB. Possible solutions I have not tried because of potential hassle that I can think of: - Update BIOS (I have the fourth latest version. I need to find a USB flash drive somewhere) - Reset CMOS (the battery is under a heatsink and some hassle to reseat. The jumper however is easier to test) All help is appreciated! Please ask for more information if I missed something relevant.