UPDATE: apparently, I misdiagnosed memory stick B. It doesn't boot up in any slot. I was led to believe it did because the motherboard would beep (one short beep, the code for successful boot for this motherboard) and I would turn it off to test other slots before I got to see the message it was going to show: "Overclocking failed. Press F1 for setup and F2 to load setup defaults."
Once I went to setup and reset the defaults and tried to boot again, it wouldn't (same symptom I described: no video, no beep).
I think then that this stick must be defective. Is there any way I can be sure?
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I bought two identical Corsair XMS2 2GB 800Mhz memory sticks and I can`t get them to work in pairs, although they work fine separately.
I`m trying to install them in a Asus P5K Deluxe motherboard. This mobo has four memory slots, two yellow (1st and 3rd from left to right) and two black (2nd and 4th).
Memory stick A (I differentiate them by the serial numbers) works solo in any of the four slots. Memory stick B, however, works fine in any slot BUT slot #1 (what seems really really strange to me). doesn't boot up.
I then tried to make them work in pairs in the yellow slots (1 and 3). The machine doesn`t boot up (fans turn on, but no video and no beep happens). If I remove either of them (leaving just one), the machine boots.
Both memories (which even have consecutive serial numbers) have 5-5-5-18 timings. My CMOS settings for DRAM timings are on auto. I tried to set them explicitly to 5-5-5-18 and the PC doesn`t boot (even with only one stick).
My situation is similar to Memory works fine separately, but not together, but I can`t even get one pair to work.
PS: I do have another pair of almost identical memories (Corsair XMS2 1GB 800Mhz, 5-5-5-12) that I want to install together with the 2GB pair, but not before I even get the 2GB pair to work.
How can I even diagnose what's to blame here?!