the biggie here is theres only the sempron socket A cpu's availiable new .. and alot of the older MB's cant run them without flashing the bios .
you could look on ebay for a barton or mobile barton cpu
you may already have a good cpu in there and its just a default clock speed .
1.9 ghz can be any thing from a 2200+, 2400+ , 2500+, 2600+ or on up to a 3200+ that is ,,, as i said is underclocked or @ default .
cpuZ or cpuid doesnt always show the cpu correctly when it comes to 32 bit AMD's windows shows these cpu's as to what there clocked at not what they actually are .
As example I can take my 2500+ MBarton and make it show up as any cpu listed or go to unknown like it is in my DXdiag (go to start/run type in Dxdiag yours may show your cpu/machine model ect ... )
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Time of this report: 10/29/2006, 11:34:11
Machine name:
Operating System: Windows 2000 Professional (5.0, Build 2195) Service Pack 3
Language: English (Regional Setting: English)
System Manufacturer: ASUSTeK Computer INC.
System Model: A7N8X-E
BIOS: Phoenix-Award BIOS v6.00PG
Processor: AMD Athlon(tm) , ~2.5GHz Memory: 1024MB RAM
Page File: 145MB used, 2317MB available
Note ; this is a 1.83ghz 2500+ M barton Over clocked on watercooling
if i set it for 2.2 ghz it shows up as a 3200+ .
so as my examples above you might be able to overclock your cpu alittle for more performance but you need to know exactly what hardware your using .along with things such as Cooling setup ..what temps your running at . what ram , and what type of powersupply is in your pc.
These barton cpu's hate to run at 54C and above , its very important to track the temps with them . (I stress this point the most )