That small PS logo is shown the 1st time you ever turn on the PS2. it's "Out of box setup" that is shown the 1st time the PS2 is turned on. If you're seeing this, it's very likely the NVRAM is now corrupted or at least it cannot read it properly... Try finishing the setup then at the browser press the triangle button and check if the model number is shown properly. (Very likely you will get "Unknown" or some garbage) If so you might have shorted bus lines in the path IOP (I/O Processor, the CXD9798GP) to the CD/DVD DSP (CXD3098Q)...
There's some 44 ohm resistor packs on the bus that love to get shorted (on the GH-026 board, so called V10) and might cause weird errors like that. Actually a lot of people are making money with this and aren't telling anyone else about it ... lol
SCPH-10000_GH-001 SCPH-15000_GH-003 SCPH-18000_GH-008 SCPH-30001_GH-005 SCPH-30000_GH-016(V4) SCPH-30001_GH-010(V4)
2xSCPH-10190, 2xSCPH-10350, 2xSCPH-10280
"**** j0 hackers!"
-Sjeep (As seen on TOXIC OS ELF...)