Fortunately we were able to borrow an HP blade to test with (ProLiant BL460c G6). We swapped in our Westmere CPUs and our RAM. We had the blade for a very limited time, so this testing was about as unscientific as you can get. We did find some interesting results but I definitely do not consider them conclusive.
We did see strong correlation between benchmark results of "good" and "bad" CPUs. They were different between HP and Dell, but the benchmark results were predictable. I tried making sure that relevant BIOS settings (e.g. hyperthreading disabled, turbo mode toggled back and forth, etc) were all the same.
- Good CPUs we tried were ~120 gflops in Dell and ~115.5 in HP
- Bad CPUs we tried were ~105 in Dell and 113.7 in HP
- Toggling turbo mode had almost no measurable effect in the HP blade
- No throttling was detected at all in the HP blade under any test scenario
Noting that is test was extremely limited and should not be considered conclusive, points to consider are:
- Dell blades get better performance than equivalent HP blades when using "good" CPUs
- HP blades get better performance than equivalent Dell blades when using "bad" CPUs
- Dell blades get extremely poor performance when using "bad" CPUs
- The HP blade has mediocre (but different) performance with "good" and "bad" CPUs
- Turbo mode didn't seem to have much of an effect on the HP blade
- The mediocre performance of HP blades using "good" CPUs is almost exactly the same as a Dell blade with turbo mode disabled.
- HP blades with "bad" CPUs show slightly reduced performance but are much faster than when those same CPUs are in a Dell blade (113.7 gflops in HP compared to 105 in Dell)
- No throttling was detected at all in the HP blade
- "Good" CPUs we tested in the HP blade were 115.5 gflops and "bad" ones were 113.7. It's not the same spread as in Dell systems, but it was measurable and repeatable with my limited testing
Please also see the other articles I wrote on this subject that are linked in the first paragraph.