Downgrade RAM and Instant Noodles

I’ve downgraded my computer. I removed the extended RAM. The bluescreen not yet show up. I’ve done the memtest86 from live CD Linux. There’s nothing wrong with the memory. But today, the blue screen shown up again and again.

It’s really disturbing me. A lot. So I decided, for a while removed the extended RAM. What’s wrong? I haven’t find the answer. I’ve update my Thinkpad BIOS. So the Controller version.

Now, while opening “heavy” application, I can cook some instant noodles