zms5063,
According to the chart of CPU's compatible with the X38 chipset:
http://ark.intel.com/products/31919/Intel-82X38-Memory-Controller#@compatibility
> the Xeon E6550 ( 2-core @ 2.13GHz) works.
There are 15, T3400's tested on Passmark Performance Test using the E6550 . Results are moderate, with CPU scores from 1382 to 1826.
The Xeon X3363 (4-core @ 2.83GHz) has two test results in the T3400, much better at 4403 and 4390.
The Xeon X3360 (=4306), X3230 (=3936), and X3220 (=3346) also work. I use an X3230 in a Precision 390 (8GB, Quadro K600 (1GB), and have good results in moderate visualization work and general use.
As you can see in the chart, there are several higher performing CPU's. On Passmark , the highest CPU scores for a T3400 are 4609 and 4594 for the X9650 (about $50, 12.15), then the next 6 are 4304 to 4335 for the Q9550. A common, good performing CPU is the Q6700 4-core 2.66GHz at 3624. The best performing 2-core is the E8500 @ 3.16GHz at a score of 2592 and these are only $10-15 on Ebay (12.15). I would suggest that today for general use today a 2-core at 2.6GHz is about the minimum to have any versatility.
Before spending anything on a T3400, analyze the total cost and the probable results. If you have to upgrade the OS or RAM, the cost may make it preferable to sell the T3400 and invest in the next generation, the T3500. The T3400 with a top system rating of 2171 has a maximum CPU speed of 2-core @ 3.16 or 4-core @3GHz , non-turbo and uses a maximum of 8GB of very hot DDR-667 RAM while a T3500 with a top system rating of 3484 uses up to to the W3690 or X5690 3.46/ 3.73GHz
6-core and up to 24GB of DDR3-1333.
I just received a couple of days ago a Precision T3500: Xeon W3530 4- core @ 2.8 /3.06GHz, ( top Passmark score in a T3500 of 5597), 4GB (2X 2GB) of DDR3-1333, a 9800 GT GPU, an SATA III WD Black 500GB, and Windows 7 Pro COA so I can load that for $0, and all for $53 + $26 shipping. I've bought 8GB (4X 2GB) of matching RAM for $44. The plan is to use my spare Quadro 4000 (2GB) and eventually move the Samsung 840 240GB SSD from a Precision T5500.
When CPU prices drop, I may replace the CPU with an X5677 3.33 /3.6GHz (Passmark top= 7046) which sell for about $50 in the Summer. This system, =$121 so far, is an example of putting the effort and cost in one generation newer may not be much more costly, and puts the hardware on a plane - CPU speeds for example, that is perfectly usable today. According to Passmark system results, the W3530 may be fine for my use for this system.
If you upgrade a T5500 or T7500, the iniital cost will be more, but these can use
dual 6- core Xeons and resale is much better. I've had very good luck with a T5500 purchased for $171 and then spending another $1,000 on.
Cheers,
BambiBoom
HP z420 (2015) > Xeon E5-1660 v2 six-core @ 3.7 / 4.0GHz > 32GB DDR3 ECC 1866 RAM > Quadro K4200 (4GB) > Intel 730 480GB (9SSDSC2BP480G4R5) > Western Digital Black WD1003FZEX 1TB> M-Audio 192 sound card > 600W PSU> Logitech z2300 > 2X Dell Ultrasharp U2715H (2560 X 1440) > Windows 7 Professional 64 >
[ Passmark Rating = 5064 > CPU= 13989 / 2D= 819 / 3D= 4596 / Mem= 2772 / Disk= 4555] [Cinebench R15 > CPU = 1014 OpenGL= 126.59 FPS] 7.8.15
Dell Precision T5500 (2011) > 2X Xeon X5680 six -core @ 3.33 / 3.6GHz,30GB DDR3 ECC 1333 > Quadro K2200 (4GB ) > Samsung 840 250GB / WD RE4 Enterprise 1TB > M-Audio 192 sound card > Logitech z313 875W PSU > Windows 7 Professional 64> HP 2711x (1920 X 1080)
[ Passmark system rating = 3671 / CPU = 14361 / 2D= 653 / 3D= 3561 / Mem= 1741 / Disk= 2249]