Blocks corrupted always with the same checksum 0x400

Question

Hello Oracle gurus,
Need your help with finding source of block corruption errors that we observe repeatedly on one system. See the error below.
Location of the corrupted block is always different, but the computed checksum is always 0x400. Only one block gets corrupted after a couple of days of stress testing. We completely re-install OS (RHEL4) and re-create DB. Still the same error with the same checksome appears, but in a different location. This happened 3 times already.
Does anybody know what 0x400 corresponds to? Is it all zeroes?
In my understanding, if the corruption was caused by a drive error, such as a single bit flip or several sectors corruption, then the computed checksum would be always different.
Is this correct? Any other ideas what can be the reason for such corruption?
Thanks a lot.
Hex dump of (file 9, block 357024) in trace file /u01/app/oracle/admin/pndb/udump/pndb_ora_13828.trc
Corrupt block relative dba: 0x024572a0 (file 9, block 357024)
Bad check value found during buffer read
Data in bad block:
type: 6 format: 2 rdba: 0x024572a0
last change scn: 0x0000.00b31c70 seq: 0x1 flg: 0x06
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x1c700601
check value in block header: 0xfcd0
computed block checksum: 0x400
Reread of rdba: 0x024572a0 (file 9, block 357024) found same corrupted data
Fri Apr 27 04:09:32 2007
Corrupt Block Found
TSN = 9, TSNAME = PN_TABL
RFN = 9, BLK = 357024, RDBA = 38105760
OBJN = 40738, OBJD = 40738, OBJECT = PN_EVENT_SESSION_1, SUBOBJECT =
SEGMENT OWNER = PNADMIN, SEGMENT TYPE = Table Segment

Answer 1

Well I understand that, however Oracle is running on higher level (application level).
It's hard to trace a potential lower level ( hardware level) problem in high level application.
The least thing you can try is find out which object this corrupted block belong if it's always same object or some pattarn you can tell then there might have something to do with Oracle.
If it's totally random then it's hard to say.
select segment_name,segment_type,owner
from sys.dba_extents
where file_id=(9)
and (357024) between block_id and block_id + blocks -1;