- Jun 21, 2003
- 9,291
- 30
- 91
Okay, I keep answering questions from people with a DFI Ultra-D mobo, about how to get it to work properly with their RAM, so I decided to just write a guide, that I can point them to in the future. Note that although I only have an Ultra-D, these same steps will work with any nForce 4 DFI motherboard.
First of all, DFI BIOS's are setup to give you extreme performance with your RAM @ it's stock speed and timings. That's fine for the people who don't want to overclock, but really, who buys a DFI motherboard, and doesn't plan on overclocking? That means that you're going to have to do a little experimentation with the numbers in your BIOS. Now, there are a few settings that are extremely important. We'll go over these first.
First, and most important for most people, is Trc. For instance, my Ultra-D defaults my PQI Turbo RAM, which has the Infineon IC's and is the same RAM as OCZ Platinum PC3200, the Patriot PC3200LL, and any other 1 GB sticks of PC3200 with stock timings of 2-3-2-5, to a Trc of 7. It won't even run a Trc of 7 at anything over 166 Mhz; I've got it at a Trc of 15 for now. The second most important subtiming is Trfc, which my BIOS "Auto"'s to 12; I have it set at 18. Are you starting to see a trend here?
The third thing that gives people problems is the Tref setting. Mine defaults my RAM to 3120, which is the same setting you'd use with Winbond BH-5. Now, it works fine at that setting, as long as I don't try to run the RAM any faster than 200 Mhz. But, I'd be giving up on 37 Mhz of RAM bandwidth, if I kept it at that setting. My RAM will do 237 @ 3-3-3-7 timings, at the Tref I run it at: 0780.
Now, the next thing that isn't always correct will be the DRAM Drive Strength. Mine defaults my RAM to Level 8, but that also costs me a bit of RAM speed, so I run it at Level 6, which is the next slower setting. That's because 8 is the fastest "strong" drive strength, and 7 is the fastest "weak" drive strength, so the next step down from 8 is 6, and the next step down from 7 is 5. Weird, I know, but useful to know. About the only RAM that requires weak settings here is TCCD or TCC5.
Also, unless you're using BH-5 or TCCD-based RAM, you'll want to change your DRAM Response Time to Normal. The default is Fast. And the last subtiming that you'll probably want to change is Idle Cycle Limit. Here, DFI defaults to the highest setting (256 cycles), which any RAM ever made can easily do. You'll most likely want to run it at 64 cycles if you have any decent RAM, and 128 with really cheap RAM. People with either BH-5 or UCCD will probably get slightly better performance @ 32 cycles, although it may affect their RAM's ability to overclock.
Now, when it comes to overclocking your processor and motherboard, there are a few things you'll want to know, also. The first is that you aren't going to be able to run your Opteron 165 or 170 @ 3 Ghz with stock vcore (called CPU VID Control in DFI BIOS's), stock LDT Voltage (this is the HTT Bus voltage), or stock chipset voltage. Running your processors and motherboard that far out of spec always requires additional voltage. If that bothers you, fine, don't overclock. And, as always, your mileage may vary, and anything you break is your fault, not AMD's, not Intel's, not DFI's, not MSI's, not OCZ's or Crucial's or Corsair's.
First of all, DFI BIOS's are setup to give you extreme performance with your RAM @ it's stock speed and timings. That's fine for the people who don't want to overclock, but really, who buys a DFI motherboard, and doesn't plan on overclocking? That means that you're going to have to do a little experimentation with the numbers in your BIOS. Now, there are a few settings that are extremely important. We'll go over these first.
First, and most important for most people, is Trc. For instance, my Ultra-D defaults my PQI Turbo RAM, which has the Infineon IC's and is the same RAM as OCZ Platinum PC3200, the Patriot PC3200LL, and any other 1 GB sticks of PC3200 with stock timings of 2-3-2-5, to a Trc of 7. It won't even run a Trc of 7 at anything over 166 Mhz; I've got it at a Trc of 15 for now. The second most important subtiming is Trfc, which my BIOS "Auto"'s to 12; I have it set at 18. Are you starting to see a trend here?
The third thing that gives people problems is the Tref setting. Mine defaults my RAM to 3120, which is the same setting you'd use with Winbond BH-5. Now, it works fine at that setting, as long as I don't try to run the RAM any faster than 200 Mhz. But, I'd be giving up on 37 Mhz of RAM bandwidth, if I kept it at that setting. My RAM will do 237 @ 3-3-3-7 timings, at the Tref I run it at: 0780.
Now, the next thing that isn't always correct will be the DRAM Drive Strength. Mine defaults my RAM to Level 8, but that also costs me a bit of RAM speed, so I run it at Level 6, which is the next slower setting. That's because 8 is the fastest "strong" drive strength, and 7 is the fastest "weak" drive strength, so the next step down from 8 is 6, and the next step down from 7 is 5. Weird, I know, but useful to know. About the only RAM that requires weak settings here is TCCD or TCC5.
Also, unless you're using BH-5 or TCCD-based RAM, you'll want to change your DRAM Response Time to Normal. The default is Fast. And the last subtiming that you'll probably want to change is Idle Cycle Limit. Here, DFI defaults to the highest setting (256 cycles), which any RAM ever made can easily do. You'll most likely want to run it at 64 cycles if you have any decent RAM, and 128 with really cheap RAM. People with either BH-5 or UCCD will probably get slightly better performance @ 32 cycles, although it may affect their RAM's ability to overclock.
Now, when it comes to overclocking your processor and motherboard, there are a few things you'll want to know, also. The first is that you aren't going to be able to run your Opteron 165 or 170 @ 3 Ghz with stock vcore (called CPU VID Control in DFI BIOS's), stock LDT Voltage (this is the HTT Bus voltage), or stock chipset voltage. Running your processors and motherboard that far out of spec always requires additional voltage. If that bothers you, fine, don't overclock. And, as always, your mileage may vary, and anything you break is your fault, not AMD's, not Intel's, not DFI's, not MSI's, not OCZ's or Crucial's or Corsair's.
Facebook
Twitter