|Subsequent to my posting last week I have read various forums, tried to understand the process of overclocking, and experimented, at length, by changing mobo straps and BIOS settings. All to no avail; it appears that overclocking is not as quite as simple as some posters suggest. My alternate approach, for improved performance has been to purchase a used Pentium 4 - 2.6GHZ - FSB @533MHZ, a new BIOS chip, and 1G of used memory. I should have all this hardware and firmware within the next week or so. In the meantime, I would like to get some feedback from those thoroughly familiar with this mobo. Here are some of my observations re mobo P4XVADS2+:|
1/It appears that this mobo automatically detects the CPU frequency and FSB speed when the processor is installed in the 478 socket. The CPU multiplier (in the BIOS settings), although it can be changed, has no effect on changing the processor speed.
2/ Two jumpers JP1A1 and JP1B1 on the mobo, which many people seem to think can be used to increase CPU frequency (in GHZ), are not for that purpose. I believe that they are used for matching the manufactured FSB output speed of the installed processor(CPU clock in MHZ). The 478 CPU socket can accommodate either a 400MHZ (4 X 100M) or 533MHZ (4 x 133M) CPU so I suspect these jumpers are used to match the CPU FSB speed.
3/Other posters have also said that the jumpers mentioned above are used to set the speed of the memory bus. This appears to be totally incorrect. The memory speed (SDRAM, at least)can be set in BIOS to 100M or 133M, or the settings in BIOS can be configured to automatically detect the speed of the installed memory. In the case of DDR memory, the 133m speed is used and doubled (effectively operating the RAM at 266M). However, as suggested by some, 333M memory is not accommodated on this mobo.
4/Another point of confusion, is the ambiguous indication that up to 4G of memory can be used on the mobo. While physically possible, only 2 memory modules (1G per slot max.)can be used at any time. The memory modules can be configured using either SDRAM (168 pin) or DDR (184 pin) modules. The selection is made by installing the desired memory module(s)in the appropriate memory slots. If using SDRAM, all J2A/B/C/D & J3A/B/C/D jumpers are left open and JP1 (3.3V) is shorted. For DDR memory, the options are the opposite i.e. J2A/B/C/D & J3A/B/C/D jumpers are shorted and JP1 (2.5V) is left open.
Since I am thinking of eventually upgrading to DDR memory I have two questions:
Does anyone know where I can purchase shorting shunts for DDR memory operation? Some are missing on my mobo and they break easily. They are 10 pin shorting shunts, about 3/4 inch long. Eight units are required to short all of the J2 & J3 pins for DDR operation.
It also appears, from reading various posts, that my mobo is rather temperamental about the quality? of memory modules. What memory modules appear to be most reliable for the P4vxasd2+ mobo? I have read somewhere that for larger memory modules (1G), ECC and Registered features are recommended. IS this overkill or a valid recommendation? Any suggestion from P4VXASD2 owners would be appreciated.