Gigahertz club...

[gkyc]

Hi,

I've got a cB0 stepping 750 that I can do 1GHz with but at vcore of 2.0. Another poster above has already mentioned and it is true: you need to test exhaustively to ensure stability. I use BurnInTest, Sandra and Prime95 to test my setup. I almost thought I had it at 1.95 but 30 minutes of BIT proved me wrong. Note that I could do 930 (7.5x124) trivially with 1.70.

FWIW, this is a rev 1.10 P2B with the Asus Sloket. However, I'm in an Antec SX1030 with four fans (very good cooling) with just a Voodoo3 3000 PCI.

George

[anvil]

George,

If you are getting up there and having stability problems, I would observe that the first problem I had was with memory that was not quite good enough (even though it was PC133). The next, and continual, problem I have is heat. You can't have cooling that is too good in my opinion.

The cpu thermistor taped to the heat sink registers 35-37 C under Prime95 loading most of the time. If I bump my 750 up to 1035, I start having Prime95 problems. Lower the temp to 28 C and the problems go away. I can even run it up to 1073, but Prime95 still fails almost immediately. Lower the temps down to 18C and I can probably make 1073 stable. I might even get to Windows at 1110, but I haven't tried yet.

Point is, if you can get to windows at a given speed, but stability is lacking, then (up to some point - the limit of the processor, I guess), you still might reach stability if you can go down with the temp far enough.

Since I am water cooled, I can check this out simply by lowering the water temp, but I only wanted 1000 to begin with, so I am a little cautious about the extremes. I don't want to ruin my processor just to satisfy my curiosity.

Also, does Sandra Burn In stress the system other than cpu and memory? (A nice thing about Prime95 is that it focuses on the cpu and memory.)And does the Voodoo 3 oc well?

anvil

[Amdntel]

I dont have the cpu but I've read that cb0 stepping arent great, think thats the prob?

[anvil]

In the 750e Database, there are not many cC0 at all. The best oc's are cB0 in that list. Could be because the cC0's are just beginning to circulate in numbers, but the gig + 750's posting here recently are cB0's I think.

Anyone out there reading this have a recent successful gig + cC0?

anvil

[gkyc]

Hi,

I'm pretty sure that my memory is not at fault since I'm using a new Crucial/Micron PC133 CAS2 DIMM. I'm not even running AGP to simplify matters. It's exactly the processor.

Upon everyone's advice, I've backed off to 930MHz (7.5x124) at 1.70v. It's perfectly stable at this speed. I'm going to buy a couple of thermister this weekend before venturing forth on 1000 again.

Sandra is definitely not very intensive cf Prime95 or BurnInTest but it's good enough to trip a marginal system. I use it because it's really quick and gives performance numbers at the same time.

George



anvil (Jun 19, 2001 11:38 a.m.):
George,

If you are getting up there and having stability problems, I would observe that the first problem I had was with memory that was not quite good enough (even though it was PC133). The next, and continual, problem I have is heat. You can't have cooling that is too good in my opinion.

The cpu thermistor taped to the heat sink registers 35-37 C under Prime95 loading most of the time. If I bump my 750 up to 1035, I start having Prime95 problems. Lower the temp to 28 C and the problems go away. I can even run it up to 1073, but Prime95 still fails almost immediately. Lower the temps down to 18C and I can probably make 1073 stable. I might even get to Windows at 1110, but I haven't tried yet.

Point is, if you can get to windows at a given speed, but stability is lacking, then (up to some point - the limit of the processor, I guess), you still might reach stability if you can go down with the temp far enough.

Since I am water cooled, I can check this out simply by lowering the water temp, but I only wanted 1000 to begin with, so I am a little cautious about the extremes. I don't want to ruin my processor just to satisfy my curiosity.

Also, does Sandra Burn In stress the system other than cpu and memory? (A nice thing about Prime95 is that it focuses on the cpu and memory.)And does the Voodoo 3 oc well?

anvil

[gkyc]

Hi,

I didn't have the patience to look up the s-code against the stepping but I note that quite a few people are hitting 1000 at ~1.85v or thereabout.

I do see that there aren't that many vintage board like my P2B on the list though. Anyone hazard a guess as to if the voltage depends on the board?

George

anvil (Jun 20, 2001 05:55 a.m.):
In the 750e Database, there are not many cC0 at all. The best oc's are cB0 in that list. Could be because the cC0's are just beginning to circulate in numbers, but the gig + 750's posting here recently are cB0's I think.

Anyone out there reading this have a recent successful gig + cC0?

anvil