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Thread ID: 90555	2008-06-07 06:54:00	FSB vs Memtest issue - Test #5 failing in odd ways..	Agent_24 (57)	Press F1

Post ID	Timestamp	Content	User
676283	2008-06-07 06:54:00	I have an issue here with an Asus P3V4X & P3 733Mhz CPU (133Mhz FSB): Memtest will give random errors on test #5 if FSB is set to 133mhz. The other odd thing is while the error is consistent, the location in memory is always different. I have tried FSB/RAM ratios of 100/100 100/133 133/100 and 133/133 and only where the FSB runs at 133Mhz does the problem appear. The RAM (which is PC133) can run at 133mhz fine, as long as the FSB is at 100mhz Now the CPU is designed to run 133Mhz FSB, the Board is designed to handle it, and the RAM is also 133mhz - what's the problem? CPU or Motherboard faulty I expect? or could it be something else?	Agent_24 (57)
676284	2008-06-07 07:57:00	Can you disable the CPU cache in the BIOS and test again?	CYaBro (73)
676285	2008-06-07 08:40:00	Can you disable the CPU cache in the BIOS and test again? I still get the problem when I disabled the cache	Agent_24 (57)
676286	2008-06-07 21:40:00	So you get problems with this ram at 133? Other than memtest? What brand is it, whats its timings?	pctek (84)
676287	2008-06-08 01:47:00	So you get problems with this ram at 133? Other than memtest? What brand is it, whats its timings? I haven't noticed any issues except memtest - is there any good real world test I could try? The RAM is rated at 133Mhz, 3-3-3-6 (which is what it's running at) It's Micron Tech (I think) 4 x 64MB sticks I only get the problem when I run the CPU at 133Mhz FSB. (Yes it's a 133Mhz CPU, nothing is getting OC'd) If I run the CPU at 100Mhz and the RAM at 133Mhz - it works fine If I run the CPU at 133Mhz and the RAM at 100Mhz it doesn't work. Any combination of settings where the CPU is running at 133Mhz FSB will give random errors (by random I mean random memory locations) on test 5 of memtest	Agent_24 (57)
676288	2008-06-08 03:00:00	I would say that the memory module is not quite fast enough to deliver data at a 133MHz rate. If the CPU asks for data at 100 MHz, it gives enough extra time for the data to stabilize and not give an erropr. Memtest tests the memory function. It is a "real world test" If it reports an error, it's finding an error. It is possible that it might not find all possible errors, but that's a different problem. ;) It could easily be "perfect" memory, in that it stores and delivers data correctly. It's just not quite fast enough to deliver data correctly at its specified rate. The fact that it's not always the same location indicates that it's the buffer between the data cells and the connector which is the problem.	Graham L (2)
676289	2008-06-08 03:06:00	I would say that the memory module is not quite fast enough to deliver data at a 133MHz rate. If the CPU asks for data at 100 MHz, it gives enough extra time for the data to stabilize and not give an erropr. Memtest tests the memory function. It is a "real world test" If it reports an error, it's finding an error. It is possible that it might not find all possible errors, but that's a different problem. ;) It could easily be "perfect" memory, in that it stores and delivers data correctly. It's just not quite fast enough to deliver data correctly at its specified rate. The fact that it's not always the same location indicates that it's the buffer between the data cells and the connector which is the problem. I don't quite follow.. How can the memory be too slow? The memory is rated for 133Mhz operation and runs fine at 133Mhz.	Agent_24 (57)
676290	2008-06-08 03:28:00	According to your posting, it gets the errors when the computer bus is at 133 MHz, and asks for data at 133MHz. It doesn't give the error when data are asked for at 100MHz. So the memory isn't working correctly at 133. When things have to happen in a 6 nanosecond period, things get critical. The extra 4 ns at 100 MHz seems to be enough for the data lines to settle so they are read correctly. It might be only a fraction of a nanosecond too slow. (Light travels about a foot in 1 nanosecond in free space; electricity travels a bit slower on a motherboard, or in a silicon chip.) The memory is rated for 133MHz. That needn't mean that that particular module actually works at 133. It seems that it doesn't, quite. :D Can you try it in a different memory socket? It's likely to be a "nearly" fast enough unit.	Graham L (2)
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