Ok my friends...

Here is some specs of my system

CPU = 3200+ Claw C0 1mb Cache
DDR = Adata Vitesta DDR500 (Hynix -D5) 2x512MB
Mobo = DFI LanParty UT NF3 250GB
PSU = Antec True Power 480W
Cpu Watercooled by EXOS

LTD = x2.5 For FSB > 300Mhz
x3 For FSB < 300

Those are timmings used for 295 2x512MB @ 1T...

Dram Frequency Set(Mhz) = 200(Mhz)(1/01)
Command Per Clock(CPC) = Enable(1T)
Cas Latency Control(tCL) = 3.5
RAS# to CAS# delay(tRCD) = 4
Min RAS# active timing(tRAS) = 06
Row Precharge timing(tRP) = 4
Row Cycle Time(tRC) = 11
Row Refresh cyc time(tRFC) = 17
Row to Row Delay(also called Ras to Ras delay)(tRRD) = 0
Write Recovery Time(tWR) = 2
Write to read Delay(tWTR) = 1
Read to Write delay(tRTW) = 5
Refresh Period(tREF) = 3632
DQS skew Control = Increase Skew
DQS Skew Value = 16 or 32 (i use 32)
DRAM Drive Strength = Level 1
Max Asynce lantency = 8
Read Preamble time = 5.5nano sec
Idle Cycle Limit = 0 or 16 (i use 0)
Dynamic Counter = Enable
R/W Queue Bypass = 8x
Bypass Max = 5x
32 byte Granulation= Disable (8burst)

Until now i manage to have 295 1:1 @ 2x512MB 1T error free on MEMTEST but 287 stable on Windows

Also using same timings using 1x512MB @1T i have 315 error free on MEMTEST+ but again ONLY 290 stable on windows....

I know its not a RAM issue but probably CPU limit for my old Claw C0 3200+ 1MB cache..
My cpu was of one the first step and is 1 year old..
So is a bad overclocker and suffer from Mem Controller instability...
I cant explain for sure why i can pass 2,5 hours wall time of 5th MEMTEST using 312 Mhz - DDR624 and when i boot into windows and try to bench using Super PI - FAST PI or a heavy 3D Bench, i get random black screens and Restart...

I will try finding out why get those problems and will inform you...