I have two machines built around ABIT IC7 G motherboards -- one in use and one on the bench. One has a P4 Northwood 3.0 GHz CPU, the other has a Prescott P4 3.0 GHz CPU. Both machines are running Windows XP with SP2 installed, although that fact is irrelevant to the problem I have encountered.
The Northwood machine was failing a Prime95 test so I ran MemTest on it and the memory showed lots of errors. The memory was OCZ PC3200 EL Platinum Rev 2, with latency specs of 2,2,2,5. Thinking the memory had gone bad, I opened a new matched pair of Corsair XMS PC3200, also with specs of 2,2,2,5, and replaced the memory. Still lots of errors. The memory addresses at which errors occur are random.
The bench machine with the Prescott is overclocked to 3.8 GHz. The FSB is 253 MHz, The memory divider is set to 5:4 so the memory is running at close to spec (202 MHz instead of 200 Mhz). The timings are set in the BIOS to 2,3,2,5 -- CAS,Act to Precharge, RAS to CAS and RAS precharge. I swapped in both the OCZ and the Corsair memory that was showing errors on the Northwood machine and no errors were shown in MemTest for either set after many hours of testing on the bench machine. The conclusion is that both memory sets are good.
I have gone back to the Northwood machine and set the memory divider so that the clock to the memory is only 180MHz. Both machines are running the memory at 2.8v, the highest the IC7 G has available. Both the OCZ and the Corsair still show errors in Memtest -- even though both are now running at under spec. I even relaxed the timing in the Northwood machine to 2,3,2,7 without getting rid of the MemTest errors.
The bottom line is that memory which works flawlessly in one IC7 G motherboard at nominal spec. (202 MHz, 2,3,2,5) fails miserably in another IC7 G motherboard at below spec (180 MHz, 2,3,2,7)
Can anyone even suggest a possible explanation for this anomolous behaviour?
The reason for the 3 setting instead of the spec 2 is that the SPD setting results in a latency setting of 2,2.5,2,5 and Eric Ryder at OCZ informed me that the OCZ memory does not like the 2.5 setting. He suggested it be set in the BIOS to 3.
Incidentally the Prescott machine -- overclocked to 3.8 GHz -- can and has run Prime 95 for 24 hours at a time. Rock stable.
The Northwood machine was failing a Prime95 test so I ran MemTest on it and the memory showed lots of errors. The memory was OCZ PC3200 EL Platinum Rev 2, with latency specs of 2,2,2,5. Thinking the memory had gone bad, I opened a new matched pair of Corsair XMS PC3200, also with specs of 2,2,2,5, and replaced the memory. Still lots of errors. The memory addresses at which errors occur are random.
The bench machine with the Prescott is overclocked to 3.8 GHz. The FSB is 253 MHz, The memory divider is set to 5:4 so the memory is running at close to spec (202 MHz instead of 200 Mhz). The timings are set in the BIOS to 2,3,2,5 -- CAS,Act to Precharge, RAS to CAS and RAS precharge. I swapped in both the OCZ and the Corsair memory that was showing errors on the Northwood machine and no errors were shown in MemTest for either set after many hours of testing on the bench machine. The conclusion is that both memory sets are good.
I have gone back to the Northwood machine and set the memory divider so that the clock to the memory is only 180MHz. Both machines are running the memory at 2.8v, the highest the IC7 G has available. Both the OCZ and the Corsair still show errors in Memtest -- even though both are now running at under spec. I even relaxed the timing in the Northwood machine to 2,3,2,7 without getting rid of the MemTest errors.
The bottom line is that memory which works flawlessly in one IC7 G motherboard at nominal spec. (202 MHz, 2,3,2,5) fails miserably in another IC7 G motherboard at below spec (180 MHz, 2,3,2,7)
Can anyone even suggest a possible explanation for this anomolous behaviour?
The reason for the 3 setting instead of the spec 2 is that the SPD setting results in a latency setting of 2,2.5,2,5 and Eric Ryder at OCZ informed me that the OCZ memory does not like the 2.5 setting. He suggested it be set in the BIOS to 3.
Incidentally the Prescott machine -- overclocked to 3.8 GHz -- can and has run Prime 95 for 24 hours at a time. Rock stable.