my spare pc engine's issues

I got this pc engine from an ebay listing that was sold as broken. I have no idea, what caused it to stop working as the listing said nothing of the matter.
Upon receiving it, I discovered that it just needed a new fuse, as the existing was blown. At the same time, I swapped the aging 7805 with a fresh one.

When I plug my turbo everdrive on my main pc engine, upon boot I get an instant white screen before I can enter the contents of my sd card.
On this machine, I get a dark blue or a purple instant screen. This has no effect on actual gameplay, grapchis or sound though so far. I have no original hucard to test its' behavior with one.
The other issue, is that the new fuse I installed managed to blow again. I had this spare stored away on a plastic bag. I replaced it again and all seems to run fine. My power supply is a 1 A switching that I use on other appliances and retro consoles with no issues for the last 1 year.

I was thinking of re-capping this machine, but upon inspection I found no leaking capacitor and abandoned the idea.