tModLoader refuses to use all of my RAM

Recently got a PC upgrade, previously I had 16GB of RAM, which TML happily uses all of. Now, I have 24GB but tMod seems to be stuck at 8GB allocated RAM and does not use the remaining 16. I thought it was some dynamic thing so I enabled 20 mods and it crashed because it exceeded that 8GB allocated RAM. I tried Minecraft Neoforge to test if all my RAM gets used and it seems to exceed 8GB so it seems that this only happens with TML. Any ideas or ways to brute force it to use all the RAM as its supposed to do?