How much would a modded Dreamcast with the following mods go for? USB GDRom from MNEMO Dual bios with switch to select stock BIOS or japanese-cake BIOS. Optional CPU overclock to 240 Mhz using a ECS-100AX-400 oscillator. There is a switch to select stock and overclock speeds. Custom heatsinks from Alpha Novatech that measure 40 mm x 40mm x 12mm for the CPU and 25mm x 25mm x12mm for the GPU. Heatsinks have also been added to the RAM. 80 watt PicoPSU (12-32v PicoPSU-80-WI-32V) with 19V 6.32A 120W AC Adapter. The 19v power adapter should help make the PicoPSU more efficient and give off less heat versus a 12v PicoPSU. Noctua NF-A4X10-FLX 5V Fan. This extra fan was added to increase airflow and help cool the CPU since it can be overclocked. The stock fan was replaced with a Copal F310RF-05LB. The new fan moves the same amount of air as the stock fan (3.2 CFM) but is much quieter at 17 dB(A). Overclocked VMU using a CA-30 crystal. The VMU has been overclocked so it will function when the Dreamcast is overclocked. The VMU will also work on the Dreamcast when it is not overclocked. Coin Cell Button Battery Socket Holder mod with Maxell ML2032 rechargable battery. Heatsinks have also been added to the PicoPSU and USB GDRom controller. While it's most likely not necessary it never hurts to have extra cooling.
Also, for the replacement exhaust fan I added an Arduno Pro Mini to emulate the Dreamcast's fan signal (as seen in this thread, thanks Compupaq!). I kept the BIOS and overclock switches inside of the Dreamcast because I like to keep the case as stock looking as possible. The switches are accessible by opening the lid.