GoKawiilFeb 16, 2025
Mo RAM, mo problems
As a retro-computer enthusiast, it seems that parts are either insanely expensive or dirt cheap. If the first case has obvious problems, the second can also lead to issues.
When I built the Quake PC, the motherboard and HDD were worth their weight in gold. But the price of RAM modules was ridiculously low. So I maxed out by buying $40,000 worth of 1997 SDRAM, namely 384 MiB, for the price of $60.
From 44 fps to 33 fps
After I got the machine working, I ran benchmarks for weeks. I was constantly swapping video-cards, changing RAM types (SDRAM, EDO), adding RAM, removing RAM, and testing different CPUs. The CPU in my collection that ran Quake the best was the Pentium MM 233MHz clocking demo1 at 44.6 fps. That figure was consistent with benchmarks of the era.
I wrote an article about winquake then took a break from 1997. A month later I had the idea to measure Michael Abrash assembly optimizations. I ran the same benchmark again. But this time I measured 33 fps. That was nearly 25% slower. What happened?
Troubleshooting
I tried pretty much everything I could think of. I swapped the graphic card, removed all the 3D accelerators, updated the drivers, downgraded the drivers, wiped the whole system, re-installed everything, double checked that I was still using the MMX 233Mhz, and verified the frequency multiplier. Still 33 fps.
Did a RAM module go bad? I tried to remove one of them. 33 fps. Remove a second one (leaving only one). Now the game ran at 44 fps. Two modules going bad? Hm, that seems weird. I tried to swap modules, leaving only one in the machine. All of them ran the game a 44 fps. Only when two of more are in the machine, the framerate drops back to 33 fps.
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