Please Help! Old Computer Upgrade (Bios Trouble)

[SpideyT]

I upgraded this emachine el1333g-01w, with 8gb of ddr2 ram, which is 4gb past what was recommended to see if it could (which it does), the emachine boots up and goes into windows 10 perfectly fine with the new upgraded processor to the amd phenom II 9850 cpu, however I want to be able to get into the bios for this emachine, but it just gets stuck on a screen with a blinking _ underscore... Also if I do nothing during the boot sequence I get the same result this one guy got on techguy, see attached link. I need help with this as I do not know what else to do, I like revising old pc's to be able to play semi-modern titles, my plan is to get into the bios to fix the ram to run at 800mhz and to actually see the cpu in the bios instead of having to boot into windows to see the cpu, as I have a feeling it is only using one core at the moment. With this said I also upgraded the Power Supply to a 600watt modular 80 plus gold, I want to get within the next couple weeks a rx 570 4G for this build, https://techguy.org/1171963