You can either invest with cash, or you can rollover your 401k/ IRA into crypto IRA. This way you can potentially earn much higher profits than with your current stock portfolio. Instead of rolling over your entire IRA/401k into Crypto IRA, you might choose to rollover part of it in gold, part of it in crypto, and yet leave the third part in traditional assets such as stocks, for diversification purposes. This is not a financial advice, always use your own discretion.