Is it worth getting this cpu ?

[nogginthenog]

I have recently bought another mobo for folding, it has a 3.06 Pentium 4 with HT and 2MB L2 cache. Is it worth buying a Pentium D 2.8 with 4MB L2 ?

I will also be running an Nvidia Cuda card on it.

[7im]

You ask worth but gave no dollar values?

[nogginthenog]

I already have the board and the P4 3.06, the D 2.8 is an ebay auction of a used item, with a fan/sink i also need. I want to know if the 2.8 will fold better, with 2 real cores and the bigger cache, compared to the P4 with HT

[7im]

Yes, the PD will fold almost double the P4, relatively speaking. But if there is a choice between adding the PD, or buying a higher end GPU, then put the funds towards the better GPU.

[nogginthenog]

Thanks. I already have a GPU to put on it.

[ChasR]

Of more concern than the ppd increase with the new cpu is the power consumption to produce relatively little ppd. Running smp on the dual core. you might make 1000 ppd and burn 7.2Kwh doing so ($.86 here in Georgia). Relative to other machines, the dual core pentium D points per Kwh is very poor. It's certainly not worth the cost of upgrading or running it to me.

[7im]

If you can spend $10 and go from P4 to a PD, then it's a good buy to go from 110 PPD to 1100 PPD.

However, I wouldn't be running hardware this old unless it were relatively free.

[csvanefalk]

This is very old hardware, so you would be much better off buying something newer - your PPD/watt efficiency should increase by at least an order of magnitude if you go for an i5 processor instead. Mobos for those are really cheap as well, and you can find some excellent deals on the CPUs themselves.

[PinHead]

Bottom line is yes. Bottom bottom line is the P4 Dual's put out a lot of heat. My P4 Dual 3.4 is idling because true quad core 2.83 puts out about half the heat. So to a previous point, even if it's free; can you stand the heat? The cost will not be the purchase, but the power bill and not just for running it but for the A.C..

[nogginthenog]

Thanks for your input folks, the heat, noise and electric bill costs are indeed of concern. I have retired from folding service a couple of machines recently, and not bothered to fix a laptop that I was going to fold on.

[nogginthenog]

OK , now I am considering another CPU, for a different mobo,
Core 2 Duo Processor E8400 6M Cache 3.00 GHz SLB9J

Is there a limit to how much benefit more L2 cache gives? I've noticed my other F@H clients don't use vast amounts of RAM, one P4 HT CPU is currently using about 46MB. I've tried upgrading memory speed as much as a mobo allows, but it didn't make much difference.

[bruce]

Memory speed, cache size, and HyperThreading are relatively unimportant. Yes, the make a small difference but things that matter most are the number of real Cores and their speed. Newer technology sometimes matters. (e.g.-The Core2 platform is better than the Pentium platform because it included a significant change in Floating Point performance that isn't obvous if you only look at MHz.)

[DoctorsSon]

A Pentium D at 2.8 will not make 1k ppd, I have 2 of them and it is closer to 800 IIRC.
I have a Core 2 Duo E6600 at 2.4Ghz it gets 1.5-2k ppd depending on WU's and how much web surfing I do..