A Japanese startup Exascaler built the first 1000+ core chip PEZY-SC. It is a 28nm MIMD processor with 1024 cores and has rankings on the Green 500.
Nvidia had 240 cores in a GPGPU chip back in 2006 and 512 core shortly thereafter.
In 2006, Intel built the 80 core the Tera-Scale Teraflop Prototype.
The UC Davis Kilocore chip is the most energy-efficient “many-core” processor ever reported. The 1,000 processors can execute 115 billion instructions per second while dissipating only 0.7 Watts, low enough to be powered by a single AA battery. The KiloCore chip executes instructions more than 100 times more efficiently than a modern laptop processor.
There is a 3 page technical paper on Kilocore - A 5.8 pJ / Op 115 Billion Ops / sec, to 1.78 Trillion Ops / sec 32nm 1000-Processor Array
1000 programmable processors and 12 independent memory modules capable of simultaneously servicing both data and instruction requests are integrated onto a 32nm PD-SOI CMOS device. At 1.1 V, processors operate up to an average of 1.78 GHz yielding a maximum total chip computation rate of 1.78 trillion instructions/sec. At 0.84 V, 1000 cores execute 1 trillion instructions/sec while dissipating 13.1 W.
SOURCES - UC Davis