3200 is 400MHz DDR and LL usually means low latency (CL2). The SDRAM you are using is definitely holding you back.
Here's a couple of my old 3dmark scores - first one was an XP 1800+ wth a GF4 Ti4200 with 512MB DDR, Asus A7V333 mobo (ignore the green UI, yes I actually thought that looked good about 10 years ago... 😒 )
Second one is an XP2800+ with Radeon 9800 Pro, and 1GB dual channel DDR, Abit NF7 mobo
These systems are long gone but I can still remember that Win 2K seemed to give me the highest 3Dmark scores , even if only a few points above XP.
Also one thing to try - launch 3Dmark, go ctrl+alt+delete, task manager, shut down ALL running processes excluding svchost and essential windows processes... but everything else, including Explorer, kill it. Then run your benchmark. This seems to be good for another few points. You can try raising priority of the 3dmark process but I never noticed a difference from this.